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In this paper, the properties of photonic band gaps (PBGs) for three-dimensional (3-D) magnetized plasma photonic crystals (MPPCs) composed of homogeneous magnetized plasma spheres immersed in the anisotropic dielectric (the uniaxial material) background with diamond lattices are theoretically studied by the plane wave expansion method, as the Faraday effects of magnetized plasma are considered. The equations for calculating the anisotropic PBGs in the first irreducible Brillouin zone are theoretically deduced. The anisotropic PBG and one flatbands region can be achieved. The effects of the ordinary-refractive index, extraordinary-refractive index, plasma filling factor, plasma frequency, and the external magnetic field on the characteristics of first anisotropic PBG are studied in detail, respectively, and some corresponding physical explanations are also given. The numerical results show that the anisotropy can open partial band gaps in diamond lattices, and the complete PBG can be obtained compared to the conventional 3-D MPPCs doped by the isotropic material (the relative bandwidth of PBG is increased by 0.1108). The bandwidth of PBG also can be enlarged by introduced the magnetized plasma into 3-D PCs containing the uniaxial material, and the relative bandwidth of PBG is increased by 0.0266. It also is shown that the first anisotropic PBG can be manipulated by the ordinary-refractive index, extraordinary-refractive index, plasma filling factor, plasma frequency, and the external magnetic field, respectively. The PBG can be enlarged by introducing the uniaxial material into 3-D MPPCs as the Faraday effects are considered. It also provides a way to enlarge the complete PBG for the 3-D MPPCs. [ABSTRACT FROM AUTHOR]

In this paper we demonstrate the design of a low-cost optical current sensor. The sensor principle is the Faraday rotation of a light beam through a magneto-optical material, SF2, when a magnetic field is present. The prototype has a high sensitivity and a high linearity for currents ranging from 0 up to 800 A. The error of the optical fibre sensor is smaller than 1% for electric currents over 175 A. [ABSTRACT FROM AUTHOR]

Abstract: The ITER ion-cyclotron range of frequency (ICRH) heating system is required to couple 20MW of power in the frequency range 40–55MHz for a large range of scenarios with Edge Localized Modes. To mitigate the associated risks, it is foreseen to design and install on ITER two port-plug antennas for a total of 20MW coupled power on long pulse operation [1]. The CEA activity to this antenna design within the CYCLE consortium was focused on the Faraday screen design (Fig. 1) and associated radio frequency (RF) sheath modelling, the reflectometers design for edge density measurement in the antenna vicinity and a contribution to the remote handling/tooling of the antenna. This paper is an overview of each item and proposes some R&D activities on key components. [Copyright &y& Elsevier]

Abstract: A novel method for measuring Faraday rotation angle by the frequency spectrum analysis is presented in this paper. The theoretical analysis and the experimental results demonstrate that Faraday rotation angle can be determined by the amplitude ratio of the signal's fundamental frequency to double frequency. A solenoid working on different voltages is used to produce different magnetic fields. The Faraday rotation angles in these magnetic fields have been measured. The linear fitting degree of the voltage and Faraday rotation angle is better than 99%. [Copyright &y& Elsevier]

To support the design of an ITER ion-cyclotron range of frequency heating (ICRH) system and to mitigate risks of operation in ITER, CEA has initiated an ambitious Research & Development program accompanied by experiments on Tore Supra or test-bed facility together with a significant modelling effort. The paper summarizes the recent results in the following areas: Comprehensive characterization (experiments and modelling) of a new Faraday screen concept tested on the Tore Supra antenna. A new model is developed for calculating the ICRH sheath rectification at the antenna vicinity. The model is applied to calculate the local heat flux on Tore Supra and ITER ICRH antennas. Full-wave modelling of ITER ICRH heating and current drive scenarios with the EVE code. With 20 MW of power, a current of ±400 kA could be driven on axis in the DT scenario. Comparison between DT and DT(3He) scenario is given for heating and current drive efficiencies. First operation of CW test-bed facility, TITAN, designed for ITER ICRH components testing and could host up to a quarter of an ITER antenna. R&D of high permittivity materials to improve load of test facilities to better simulate ITER plasma antenna loading conditions. [ABSTRACT FROM AUTHOR]

This paper examines the radiative transfer of synchrotron radiation in the presence of a magnetic field configuration resulting from the compression of a highly disordered magnetic field. It is shown that, provided Faraday rotation and circular polarization can be neglected, the radiative transfer equations for synchrotron radiation separate for this configuration, and the intensities and polarization values for sources that are uniform on large scales can be found straightforwardly in the case where opacity is significant. Although the emission and absorption coefficients must, in general, be obtained numerically, the process is much simpler than a full numerical solution to the transfer equations. Some illustrative results are given and an interesting effect, whereby the polarization increases while the magnetic field distribution becomes less strongly confined to the plane of compression, is discussed. The results are of importance for the interpretation of polarization near the edges of lobes in radio galaxies and of bright features in the parsec-scale jets of active galactic nuclei, where such magnetic field configurations are believed to exist. [ABSTRACT FROM AUTHOR]

[Display omitted] • Achiral TbIII-inorganics revealed MCPL spectra under 1.7 T external magnetic field. • MCPL characteristics depended on GdIII and YIII coexisting in the TbIII-inorganics. • Interplay between TbIII and GdIII/YIII may affect a performance of MCPL materials. The present paper reports on three new achiral terbiumIII inorganics that emit strong green-color magnetic circularly polarized luminescence (MCPL) (| g MCPL | ≤ 5.4 × 10−3 T−1 at 490–550 nm) when embedded in a KBr pellet in the presence of a 1.7 T external magnetic field. The signs of the green MCPL spectra are controllable by altering the S-up and N-up directions of the external magnetic field. Divalent manganeseII and trivalent terbiumIII emit similar green luminescence; however, their wavelengths and MCPL characteristics are very different. Hence, we anticipate that these green-color MCPL substances can be used as new security pigments. [ABSTRACT FROM AUTHOR]

• Two defective conjugated magneto active photonic crystals are proposed. • 4 × 4 Transfer matrix method is utilized to extract the optical response of the structures. • The dependence of the crystals' transmittance on the period number of the layers are investigated. • Optical anisotropy of the crystals is considered to be purely magnetic field-induced. • The connection between light incident angle and magneto-optical effects are discussed. Two defective conjugated magneto active photonic crystals are proposed in this paper for fabrication of Faraday rotators. Optical features of the suggested structures are studied using 4 × 4 transfer matrix method and taking into consideration of the couplings of polarization states. Band structure of the crystals including generation of stop bands and resonant modes localizations are studied by exploring the dependence of the crystals' transmittance on the period number of the layers. It is shown that desirable responses are obtained by just very low number of periods. Furthermore, optical anisotropy of the crystals is considered to be purely magnetic field-induced. Then in addition to studying the dependencies on structural parameters, connection between wave incident angle and magneto-optical effects (Faraday rotations and changes of the ellipticity angle) are discussed in detail. Results clearly show the ease of tunability of the structures' responses in this way which is of prime importance from experimental point of view. Furthermore, the proposed structures offer remarkable Faraday rotation angles when transmittance amounts remain high enough simultaneously. Thus it seems that these crystals might be useful for fabrication of polarization dependent sensor/transducers based on Faraday rotators which are vital elements in development of integrated circuits as well as imaging systems. [ABSTRACT FROM AUTHOR]

Some 175 years ago Michael Faraday discovered magnetic circular birefringence, now commonly known as the Faraday effect. Sensing the magnetic field through the influence that the field has on light within the fiber optic sensor offers several advantages, one of them fundamental. These advantages find application in the measurement of electric current at high voltages by measuring the induced magnetic field, thus warranting application for this kind of fiber optic sensor (FOS) in future smart grids. Difficulties in designing and manufacturing high-performance FOSs were greatly alleviated by developments in optical telecommunication technology, thus giving new impetus to magnetometry based on the Faraday effect. Some of the major problems in the processing of optical signals and temperature dependence have been resolved, yet much effort is still needed to implement all solutions into a single commercial device. Artificial structures with giant Faraday rotation, reported in the literature in the 21st century, will further improve the performance of FOSs based on the Faraday effect. This paper will consider obstacles and limits imposed by the available technology and review solutions proposed so far for fiber optic sensors based on the Faraday effect. [ABSTRACT FROM AUTHOR]

This paper treats the relaxation of a magnetic field into a minimum-energy force-free state in a cold (pressure-less) viscous fluid, under the frozen-in condition of perfect electrical conductivity and letting the viscosity-dissipated energy be completely lost. A non-Newtonian fluid in popular use is studied in relation to the Newtonian viscous fluid, as two alternative numerical means to (1) construct force-free fields representing solar coronal structures in realistic geometry and (2) investigate the Parker theory of spontaneous formation of electric current sheets as a basic MHD process. Faraday's induction equation imposes an independent condition on the fluid velocity at rigid, perfectly conducting boundaries. This boundary condition is quite compatible with Newtonian mechanics but not with the non-Newtonian fluid model where velocity is equated to the Lorentz force with a free, positive multiplicative-factor. This defining property gives rise to unphysical or artificial singularities not previously known that are completely distinct from the physically admissible singularities representing the current sheets of the Parker theory. In particular, the non-Newtonian fluid takes amagnetic field with neutral points from any one of a continuum of initial states into an unphysical state instead of the proper force-free end-state accessible by Newtonian relaxation. The validity of previously published MHD results based on this non-Newtonian fluid, including some counterclaims against the Parker theory, is dubious. Investigating the Parker theory requires numerical relaxation models capable of anticipating and accurately describing inevitable current-sheet singularities. By including a weak resistivity to dissipate the inevitable current sheets as they form, the field can change topology intermittently to seek a terminal force-free state free of singularities. The minimum-energy state of this more complete model corresponds to the long-lived relaxed structures in the corona. [ABSTRACT FROM AUTHOR]

The depolarization asymmetry seen in double-lobed radio sources, referred to as the Laing-Garrington (L-G) effect where more rapid depolarization is seen in the lobe with no visible jet as the wavelength increases, can be explained either by internal differences between the two lobes, or by an external Faraday screen that lies in front of only the depolarized lobe. If the jet one-sidedness is due to relativistic beaming the depolarization asymmetry must be due to an intervening Faraday screen. If it is intrinsic the depolarization asymmetry must be related to internal differences in the lobes. For a random viewing angle distribution, which must be the case here where un-beamed lobe radiation dominates, jet one-sidedness is unrelated to viewing angle and therefore cannot be used either to estimate the viewing angle or to imply beaming. The outflow speed in the kpc jet is notoriously difficult to determine. However, although it has not yet been proven conclusively, we assume in this paper that the speed in the outer jet of several Fanaroff-Riley Class 1 (FRI) sources exhibiting the L-G effect is close to the 0.1c reported by several other investigators. For these sources we find that the jet one-sidedness cannot be explained by beaming and therefore must be intrinsic. In these FRI sources the L-G effect must be due to differences that originate inside the lobes themselves, with the outer regions of the relevant lobe acting as a Faraday screen. Although it is not known if the flow in the outer jets of FRII sources also slows to this speed it is suggested that the explanation of the L-G effect is likely to be the same in both types. This argument is strengthened by the recent evidence that FRII galaxies have very large viewing angles, which in turn implies that the L-G model cannot work regardless of the jet velocity. It may therefore be too soon to completely rule out internal depolarization in the lobes as the true explanation for the L-G effect. [ABSTRACT FROM AUTHOR]

Mueller matrix measurements are most commonly performed using a set of polarization state generating (PSG) optics and an independent set of polarization state analyzing (PSA) optics. However, for polarized confocal microscopy and polarization sensitive optical coherence tomography it would be advantageous if the same set of polarization optics could be used for both PSG as well as PSA. This has not been possible because, in this configuration, a complete set of incident and analyzer states cannot be generated using polarizers and waveplates alone. In an earlier attempt to address this issue it was shown that by using two Faraday rotators, with independently variable circular retardance, in the polarization optics, complete Mueller matrix measurement can be performed. However, a practical implementation of this approach has proved to be dif?cult due to the requirement to vary the circular retardance. In this paper we show that by incorporating only one Faraday rotator in the polarization optics, one can generate the complete set of incident and analyzer states required for Mueller matrix measurements without the need to vary the circular retardance of the Faraday rotator. [ABSTRACT FROM AUTHOR]

This paper presents feasible experimental schemes to realize controlled teleportation protocols via photonic Faraday rotations in low-Q cavities. The schemes deal with controlled teleportation of superposition states and two-particle entanglement of atomic states. The information is encoded in lambda configured three-level atoms trapped inside coupled cavities by optical fibers. Also, we estimate the success probability and the current feasibility of the schemes. [ABSTRACT FROM AUTHOR]

A new method for magnetic field generation is presented that enhances the reliability of fiber-based interferometric switches. Suitable switching technologies have been proposed and implemented, but magneto-optic (MO) materials have shown promise in realizing all-optical switching with reasonable power, loss, and switching speed. However, bottlenecks in field generation drivers have limited the performance of MO devices in fiber-based switches. Improving the design of the field generation system will enhance this technology, ultimately realizing practical and reliable solutions. Conventional drivers in MO switching devices utilize one coil with a low number of turns to quickly magnetize the MO material. This, in effect, leads to a fast optical rise time. However, the optical fall time is determined by the response of the MO material and the decay rate of any trapped magnetic energy in the coil, which can be sluggish. The proposed design achieves fast optical fall time by better controlling the demagnetization of the MO material. In this paper, the design of the magnetic field generation system is presented and compared to other recently proposed systems, the electrical system is characterized, and the reliability of the optical output is investigated. [ABSTRACT FROM AUTHOR]

ABSTRACT The contribution from the residuals of the foreground can have a significant impact on the temperature maps of the cosmic microwave background (CMB). The most powerful residuals of the foreground are found in the Galactic plane. However, in this paper, we will focus on the possible foreground contamination from sources outside the Galactic plane in the CMB maps. We will analyse the correlation between Faraday rotation maps and CMB temperature maps. A map of the Faraday rotation is dependent on the Galactic magnetic field, as well as the thermal electron density, and both may contribute to the measurement of the CMB temperature. We find that the standard deviation for the mean cross-correlation deviates from that of simulations at the 99.9 per cent level. Additionally, a comparison between the CMB temperature extrema and the extremal points of the Galactic Faraday depth is also performed, showing overlap for localized areas. Also, we find that the CMB cold spot is located at an area of strong negative cross-correlation, meaning that it may be explained by a Galactic origin. Further, we investigate nearby supernova remnants in the Galaxy traced by the Galactic radio loops. These supernova remnants are located at high and low Galactic latitudes, and thus well outside the Galactic plane. We find some correlation between the Galactic Faraday depth and the CMB temperature at select radio loops. This indicates that the Galactic foregrounds may affect the measured CMB temperature at high Galactic latitudes. [ABSTRACT FROM AUTHOR]

In the framework of the ion cyclotron resonance heating (ICRH) development led at CEA Cadarache, an actively cooled Faraday screen (FS) prototype with cantilevered horizontal bars and a slotted box has been designed to increase the heat exhaust capability (for high-power operation), reduce the parallel RF electric field along long field lines and qualify alternative mechanical solutions for ITER (bars are disconnected from the septum to reduce the stress level). The new FS has been installed on an existing ICRH antenna, and was tested during the 2011 Tore Supra experimental campaign. The antenna hosting the new screen exhibits high sensitivity to the edge plasma condition, some instabilities of electrical matching and improved heat exhaust capabilities in accordance with the thermomechanical design. RF-induced heat loads derived from IR thermography have been found to be about five times higher in the equatorial plane with the new design compared with the conventional design. The experimental results show that minimizing the parallel RF electric field along long field lines is not enough to reduce the wave-plasma interaction on the screen. This paper summarizes the experimental RF-induced heat load for several plasma scenarios and edge parameters (plasma current, density and heating power level) with emphasis on RF-sheath rectification and E × B convection generated in front of the antenna through the differential biasing of adjacent field lines [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report a Doppler lidar in which the laser frequency is stabilized and the backscattered light frequency is discriminated by a multi-peak and a less-peak atomic Faraday anomalous dispersion optical filter (FADOF), respectively. The transmission spectrum of the FADOF is stable as it is based on an atomic transition, and slightly tunable with a magnet due to Zeeman effect. The high frequency stability of the FADOF provides a high velocity accuracy; and the tunability of the FADOF transmission spectrum makes the measurement range flexible. We describe an experimental lidar system based on cesium FADOFs, and the experimental error is of±0.74m/s over velocities ranging from −40 to +40m/s. [Copyright &y& Elsevier]

Abstract: The transmission and polarization properties of Fiber Bragg Grating (FBG) with Faraday Effect are studied in this paper. The evolutions of transmission spectrum for different circular birefringence, grating parameter (physical length, index modulation) and input polarizations are simulated with Jones Matrix method. It is demonstrated that the monitoring of the 3rd normalized Stokes parameter peak values provide a new magnetic field measurement. The magnetic field strength sensitivity value is 1.482×10−5/Gs by using the optical vector analyzer whose precision is 10−5 in experiment and a very good agreement between theory and experience is reported. [Copyright &y& Elsevier]

Recently Kahniashvili et al.9 presented a unified treatment for ultraviolet Lorentz violation (LV) testing through electromagnetic wave propagation in magnetized plasmas, based on dispersion and rotation measured data. Based on the fact discovered recently by Kostelecky et al., 3 that LV may place constraints on spacetime torsion, in this paper it is shown that on the limit of very low frequency torsion waves, it is possible to constraint torsion from Faraday rotation and CMB on a similar fashion as Minkowski spacetime plus torsion. Here, the Maxwells modified equations are obtained by a perturbative method introduced by de Sabbata and Gasperini [Introduction to Gravitation (World Scientific, 1980)]. Torsion is constraint to QCMB≈10-18GeV which is not so stringent as the 10-31GeV obtained by Kostelecky et al. However, Gamma-Ray Bursts (GRBs) may lead to the more string value obtained by Kostelecky et al.Another interesting constraint on torsion is shown to be placed by galactic dynamo seed magnetic fields. For torsion effects be compatible with the galactic dynamo seeds, one obtains a torsion constraint of 10-33GeV which is two orders of magnitude more stringent that the above Kostelecky et al. limit. [ABSTRACT FROM AUTHOR]

This paper investigates the potential of graphene nonreciprocal gyrotropy for microwave applications. First, the problem of a plane wave obliquely impinging on a graphene sheet is analyzed to provide physical insight into the fundamentals of graphene gyrotropy. It is found that graphene rotates the polarization of any plane wave impinging on it. The rotation angle is larger for H-polarized oblique waves than for normally incident waves and increases as the angle of incidence increases. The opposite holds for E waves. A general transmission matrix model is then developed for an arbitrary cylindrical waveguide and for a graphene sheet inside such a waveguide. This model is next applied to a circular cylindrical waveguide loaded with one or several graphene sheets and excited in its dominant H11 mode. Although the rotation angle from a single graphene sheet is quite high at high chemical potential, the corresponding transmission level is small due to the poor matching associated with the high density of the sheet. This fact prohibits the cascading of graphene sheets with high chemical potential as an approach to increase the amount of rotation. However, by decreasing the chemical potential, graphene may be well matched to waveguide modes, and therefore a large number of graphene sheets (ten in this study) may be used to produce a significant amount of rotation with relatively low insertion loss. [ABSTRACT FROM PUBLISHER]

This paper presents the results of a study on electrogeneration of aluminium, as a coagulant to remove silica in make-up water for cooling towers. Three electrochemical systems were tested, two with aluminium electrodes (one with polarity change and another without it), and a third one with aluminium anodes and cathodes of stainless steel. From the obtained results it was concluded that under the studied conditions, the most advantageous system to produce aluminium and remove silica is the one with both electrodes of aluminium working with direct current. Due to chemical production of aluminium at the cathode, the concentration of aluminium in the water at the outlet of the electrochemical reactor is much higher than the one calculated according to Faraday's law. Under the tested conditions it was possible to remove up to 66% of silica from water containing around 50 mg L-1. [ABSTRACT FROM AUTHOR]

Abstract: Theoretical equation of Faradaic impedance (Z F) of a mediator-type enzyme-functional electrode is derived by introducing a new theoretical model in which the diffusion of mediator and substrate, enzymatic reaction and electrode reaction are considered. The typical Faradaic impedance spectrum describes the locus of the semicircle in the Nyquist plot, due to the electric double layer capacitance and charge transfer resistance of the mediator on the electrode surface. The finite diffusion impedance is also observed whose locus shows straight line of 45° to real axis and converges on real axis in the low frequency limit. In the present paper, the behaviors of the Faradaic impedance are discussed by changing in the simulation parameters including the electrode potential, diffusion coefficients, and enzymatic reaction constant. [Copyright &y& Elsevier]

In this paper, we extend our previous template analysis of a self-exciting Faraday disc dynamo with a linear series motor to the case of a nonlinear series motor. This introduces two additional nonlinear symmetry-breaking terms into the governing dynamo equations. We investigate the consequences for the identification of a possible template on which the unstable periodic orbits (UPOs) lie. By computing Gauss linking numbers between pairs of UPOs, we show that their values are not incompatible with those for a template for the Lorenz attractor for its classic parameter values. [ABSTRACT FROM AUTHOR]

This paper expounds on the optimization of magnetooptic devices using preferential domains that switch at low field strengths. In particular, an all-optical switch for transparent networks based on the Mach-Zehnder interferometer configuration is examined in detail. The switch utilizes bismuth-substituted iron garnets with a specific composition of (Bi1.1Tb1.9)(Fe4.25Ga0.75)O12 as Faraday rotators. It is proposed that switch figures of merit can be improved by preferentially choosing domains which align with applied fields at field strengths much lower than required by the bulk material. Measurement of magnetic domain orientation in the material and Faraday rotation within domains is reported. The domain behavior in low magnetic fields is also investigated to achieve a switch with lower switching times and higher extinction ratios. [ABSTRACT FROM AUTHOR]

Abstract: Thermal ionization mass spectrometry (TIMS) is a well established instrumental technique for providing accurate and precise isotope ratio measurements for elements with low first ionization potential. In the nuclear domain, particularly for the study of spent nuclear fuel sample solutions, the reduction of quantities is an important issue in order to decrease the analyst exposition to the radioactive samples. This paper presents experimental results obtained for picogram quantities of samples using electron multipliers (Channeltrons) implanted on the new generation of TIMS associated with the total evaporation (TE) acquisition method. TE method presents some advantages for the measurement of low quantities of samples in relation to the whole sample consumption and the integration of the whole signal. For this study, a Thermal Ionization Mass Spectrometer from IsotopX (Isoprobe-T) equipped with a multi-collector system including Faraday cups and four movable Channeltrons is used. This work is focused on lanthanide elements, and particularly europium, in relation to the importance of their characterization in the spent fuel to validate neutronic calculation codes. In a first approach, europium isotopic ratios by total evaporation method using Faraday cups are obtained for quantities down to 250pg. The results obtained by TE (Faraday cups only) on such low quantities confirm the potentialities of the method. A reproducibility of 2.5‰ (k =2), was obtained on the 153Eu/151Eu ratio (n =11), for natural samples with an accuracy around 1‰. In a second approach the same procedure is tested on Channeltron detectors by reducing the amounts of samples (from 50pg to 1pg). In order to obtain accurate isotope results, intrinsic parameters such as applied voltages, dead time and noise were determined. A Channeltron specific intercalibration gain method was also developed, as this parameter was found to be the major source of uncertainties using this type of detectors. The reproducibility on the 153Eu/151Eu ratio was respectively found around 3% (k =2). These results show the potentialities of isotopic measurements of sub-nanograms quantities and the different sources of uncertainties using total evaporation and Channeltrons on the Isoprobe-T. [Copyright &y& Elsevier]

Abstract: A magnetic or an electrical field applied to a metallic specimen will be distributed according to the properties of the crack in the specimen. Researchers have used the finite element method (FEM) to simulate the distribution of an alternating magnetic field around a crack on a paramagnetic material. However, the simulation using this method becomes complex and time-consuming depending on the degree of accuracy desired. In this paper, we suggest a new, easier method, using dipole model (DM). The simulated results from this new method are verified by comparing them to the experimental results obtained by using Magneto-Optical/Eddy Current Imager system. [Copyright &y& Elsevier]

In recent years, significant progress has been made in developing theory and methods for modeling, detecting, and correcting ionospheric effects in low-frequency synthetic aperture radar (SAR) data. While a large number of correction methods have been developed that differ in sensitivity, data needs, and spatiotemporal accuracy, a lack of performance requirements for ionospheric correction has prevented an evaluation of their suitability for operational implementation. Hence, this paper focuses on the development of performance requirements for the correction of ionospheric effects in low-frequency SAR data. The requirements are derived considering the data quality needs of a set of SAR applications and will ensure the SAR data after ionospheric correction to meet calibration specifications and maintain full performance during all ionospheric conditions. The proposed requirements can serve as a benchmark for a performance assessment of ionospheric correction methods and will help define their suitability for operational implementation. Requirements are determined for SAR polarimetry, SAR imaging, SAR interferometry, and ionospheric research. [ABSTRACT FROM AUTHOR]

This paper presents a newly developed comb-shaped Faraday shield for high frequency (HF) planar transformers. High power density and small size planar transformers are widely used in switching mode power supplies (SMPS) as magnetically coupled devices. However, the intra-winding capacitance couples HF noise from the primary winding to the secondary winding. The coupling capacitance can cause serious common mode problems, and thus the design may not be electromagnetically compatible with the surrounding environment. The tradeoff between the leakage inductance and the coupling capacitance becomes problematic for high frequency applications. The coupling capacitance can be reduced either by increasing the separation distance between the primary and the secondary windings or by inserting a conventional Faraday shield. The former may cause the leakage inductance to increase and further increase the insertion losses, whereas the latter would result in a serious demagnetizing problem in a HF planar transformer. These problems can be resolved by using a novel comb-shaped Faraday shield. [ABSTRACT FROM AUTHOR]

This paper proposes a hula-hoop energy-harvesting system that integrates a hula-hoop motion transformer with an electromagnetic generator. The hula-hoop motion transformer converts the linear motion from environment, machinery, or even human body into rotational one under specifically designed dynamic conditions. Then, the system can generate power through electromagnetism after combining the electromagnetic generator with the rotational motion. The equations prescribing the relation between induced voltage and power for the system are derived according to Faraday's theory. Meanwhile, the physical model of energy-harvesting system is established and the governing dynamic equations are derived as well via the Lagrange's equations. Good agreement of induced voltage and power between theoretical and experimental results is obtained. The maximum power that the system can generate is approximately 5 mW when the frequency and amplitude of the external excitation are 8 Hz and 11.2 N, respectively. [ABSTRACT FROM AUTHOR]

The quality of polarimetric synthetic aperture radar (PolSAR) imagery and its polarimetric decompositions depends on the accuracy of polarimetric observations of the SAR system and its calibration. Polarization distortions on the polarimetric measurement can be incurred due to nonideal system polarization quality and propagation factors, such as channel imbalance, crosstalk, and Faraday rotation at lower frequencies. All these distortions have varying impacts on different target types as well as different decomposition methods. In this paper, we assess the polarization quality of the PolSAR system in the context of polarimetric imagery analysis and quantify the various effects of polarization distortions on polarization target decompositions. A generic metric is defined to measure the polarization purity of the system. Considering the fact that target decomposition plays an important role in imagery analysis, we apply several widely used decomposition methods to showcase the polarimetric system requirement based on the defined metric. We demonstrate that this metric can be used for radar system design and polarimetric data calibration. [ABSTRACT FROM PUBLISHER]

Reinforcement corrosion owing to chemical attack could lead to premature steel-mortar debonding, concrete cracking, and catastrophic failure of structures if not well attended. In conventional design and maintenance practices, heterogeneous concrete matrix is commonly treated as a homogeneous medium when the evolution of chemical ingress and concrete cracking need to be determined. Such oversimplification has caused significantly inaccurate prediction and evaluation of structural service life. This paper presents a finite-element (FE) model developed to evaluate the service life of reinforced concrete (RC) structures in three key steps: chemical ingress, steel corrosion, and concrete cracking. The mass conservation principle is employed in the first step to model the ingress of multiple chemical species into variably saturated heterogeneous concrete matrix. By using Faraday's law, steel corrosion and the incurred diametric expansion are then formulated as a transient displacement boundary condition for subsequent analysis of concrete cracking. The cracking pattern of concrete under the expansion force of corrosion products is finally characterized by using a cohesive-fracture approach. The FE model is validated with laboratory experiments. [ABSTRACT FROM AUTHOR]

The improvement of a low concentration gas detection system based on the intracavity fiber laser is proposed in this paper. The sensitivity of the system is deduced based on Lambert-Beer law. The optimized system was established with the gas cell made elaborately. In order to apply the wavelength sweeping technique, the fiber Bragg grating reflector was substituted by the wavelength independent Faraday rotation reflector. The sensitivity of the system for acetylene detection is reduced to less than 100 ppm by using the average of three absorption spectra. The acetylene detection coefficients of variation with different concentrations are measured. The gas measurement system is validated to detect low concentration gas effectively. [ABSTRACT FROM AUTHOR]

The third Stokes parameter will be observed from space for the first time at L-band by the Soil Moisture and Ocean Salinity and Aquarius/SAC-D satellites. The correlation between polarizations, which is the source of the third Stokes parameter, is of interest at L-band to measure Faraday rotation and also to indicate novel features of the surface. However, spurious signals (false indication of correlation) can occur in the third Stokes parameter. For example, this happens when the radiometer crosses boundaries associated with a large change in brightness temperature, such as land–water boundaries. In this paper, calculations with the Aquarius radiometer antennas will be used to show that these spurious signals are due to the cross-polarization coupling and large beamwidth associated with realistic L-band antennas in space. [ABSTRACT FROM AUTHOR]

Abstract: The far infrared transmittances and Faraday rotation effect in one-dimensional photonic crystals that contain magnetic microcavities are calculated with the transfer matrix method. The different stacking sequences of dielectric layers in the magnetic photonic crystal are considered in this paper, and the linewidths of transmission peaks and localised light of the photonic crystals are discussed. The enhancement of Faraday rotation is presented in the magnetic photonic crystals, and the largest rotation angle at the frequency of the transmission peak is 29°mm−1, which is larger than previous results. [ABSTRACT FROM AUTHOR]

Biomimetic membranes (BMM) based on polymer filters impregnated with lipids or their analogues are widely applied in numerous areas of physics, biology, and medicine. In this paper we report the design and testing of an electrochemical system, which allows the investigation of CO2 transport through natural membranes such as alveoli barrier membrane system and also can be applied for solid-state measurements. The experimental setup comprises a specially designed two-compartment cell with BMM connected with an electrochemical workstation placed in a Faraday cage, two PH meters, and a nondispersive infrared gas analyzer. We prove, experimentally, that the CO2 transport through the natural membranes under different conditions depends on pH and displays a similar behavior as natural membranes. The influence of different drugs on the CO2 transport process through such membranes is discussed. [ABSTRACT FROM AUTHOR]

Experiments designed to measure the redshifted 21-cm line from the epoch of reionization (EoR) are challenged by strong astrophysical foreground contamination, ionospheric distortions, complex instrumental response and other different types of noise (e.g. radio frequency interference). The astrophysical foregrounds are dominated by diffuse synchrotron emission from our Galaxy. Here we present a simulation of the Galactic emission used as a foreground module for the Low Frequency Array (LOFAR)-EoR key science project end-to-end simulations. The simulation produces total and polarized intensity over maps of the Galactic synchrotron and free-free emission, including all observed characteristics of the emission: spatial fluctuations of amplitude and spectral index of the synchrotron emission, together with Faraday rotation effects. The importance of these simulations arises from the fact that the Galactic polarized emission could behave in a manner similar to the EoR signal along the frequency direction. As a consequence, an improper instrumental calibration will give rise to leakages of the polarized to the total signal and mask the desired EoR signal. In this paper, we address this for the first time through realistic simulations. [ABSTRACT FROM AUTHOR]

Abstract: Diagnostic information about the self-generated magnetic fields (SGMF) generated in laser produced plasmas is normally obtained by measuring the Faraday rotation angle (FRA) of a linearly polarized laser probe beam passing through the plasma. Simultaneous recording of the corresponding interferogram is required to get the density information necessary for estimating the magnetic field. The problem with this method is that the visibility of the fringes in the interferogram can be poor, and the SGMF cannot be calculated in the regions where the interference fringes are not observable. In this paper, we propose a new method to obtain the density distribution and the SGMF from two simultaneous measurements of FRA using two probe beams of different colors, which allows one to calculate the SGMF without the need of interferometry. [ABSTRACT FROM AUTHOR]

The far-infrared polarimeter at JET is affected by an anomaly that makes difficult the interpretation of both Faraday and Cotton–Mouton effect measurements. The anomaly is clearly displayed during calibration operations in the absence of plasma: As the polarization of the probing beam is rotated, the phase shift of the polarimetric signal with respect to the interferometric signal is not constant, as expected, and changes significantly. It affects all the polarimetric measurement channels and has so far been removed by an empirical preprocessing of the raw data. It can be ascribed to a nonideal behavior of some optical components. Looking for a possible explanation of the anomaly, in this paper, we analyze the optical setup of the JET polari–interferometer according to the laws of classical polarization optics. At first, the optical characteristics of the recombination plates are analyzed in detail. Although they produce ellipticity in the transmitted and reflected beams, the results show that the recombination plates should not be responsible of the anomaly of the polarimeter. Then, the dielectric waveguides used to transfer the recombined beams from the torus hall to the detectors are, for the first time, considered as a possible origin of the anomaly. The anomalous behavior is expected to be mainly originated by reflections on metal mirrors, which may produce rotations of the polarization of the beams. A calculation has been performed in order to analyze the effects of a rotation of the polarization of the recombined beam on the detector signals. As a result, a rotation of the polarization along the line could explain the anomaly. We also suggest some simple and feasible tests, which are useful to give an experimental support to this conclusion, and discuss possible modifications of the optical setup to remove or greatly reduce the anomaly in future measurements. [ABSTRACT FROM PUBLISHER]

In this paper, an instrumentation of the Earth's field nuclear magnetic resonance (EFNMR) inside a laboratory is presented. A lock-in analysis (LIA) technique was proposed to enhance the signal-to-noise ratio (SNR). A SNR of 137.8 was achieved in a single measurement for 9 ml tap water, and the LIA technique significantly enhanced the SNR to 188 after a 10-average in a noisy laboratory environment. The proton-phosphorus coupling in trimethyl phosphate ((CH3O)3PO) with J-coupling J[H,F]=(10.99±0.013) Hz has been demonstrated. The LIA technique improves the SNR, and a 2.6-fold improvement in SNR over that of the frequency-adjusted averaging is achieved. To reduce the noise in EFNMR, it was suggested that the LIA technique and the first order gradient shim be used to achieve a subhertz linewidth. [ABSTRACT FROM AUTHOR]

The paper presents a study of Faraday rotation (FR) angle and Cotton-Mouton (CM) phase shift measurements to determine their mutual interaction and the validity of the linear models presently used in equilibrium codes. Comparison between time traces of measurements and model calculations leads to the result that only an exact numerical solution of Stokes equations can reproduce in all the experimental data. As a consequence, approximated linear models can be applied only in a limited range of plasma parameters. In general, the nonlinear coupling between FR and CM is important for the evaluation of polarimetry parameters. [ABSTRACT FROM AUTHOR]

The Faraday, magnetic circular dichroism and Kerr effects are three important magneto-optic effects. They are significant in fundamental science and applications. Presently, scientists in this field believe that Faraday and Kerr effects are caused by the difference in real parts of the refractive indices of the magnetic crystal for left-and right-circularly polarized light and that magnetic circular dichroism is caused by the difference in the imaginary parts of the refractive index (absorption) of the magnetic crystal for left-and right-circularly polarized light. However, the derived equations for these effects are approximate only. In our paper we obtain accurate formulations for these effects and find that there are mistakes in the present conclusions with respect to the above-mentioned effects. The precise equations and conclusions from our derivation are presented. [ABSTRACT FROM AUTHOR]

Abstract: We have revealed from a numerical study that the Hall plateaus are retained in the optical Hall conductivity in the ac () regime in both of the ordinary two-dimensional electron gas and graphene in the quantum Hall regime, although the plateau height in ac deviates from integer multiples of . The effect remains unexpectedly robust against a significant strength of disorder, which we attribute to an effect of localization. We predict the ac Hall plateaus are observable through the Faraday rotation with the rotation angle characterized by the fine-structure constant . In this paper we clarify the relationship between plateau structures and the disorder strength by performing numerical calculation. [Copyright &y& Elsevier]

The potential of compact polarimetry (CP) mode at longer wavelengths in a space environment for surface parameter estimation is investigated. CP consists of transmitting a single polarization while receiving two polarizations. At longer wave-lengths, one of the main challenges associated with CP from space is Faraday rotation (FR) estimation and correction. In this paper, an estimation procedure for FR is presented, which relies on the scattering properties of bare surfaces. The selection of the bare surfaces is based on a new parameter, the conformity coefficient computed from CP measurements. This parameter is shown to be FR invariant. Once estimated, the FR can be corrected over the whole image. A simple approximation to δHH° and δVV° based on CP measurements over bare soil surfaces is presented, from which soil moisture can be estimated using the 1995 Dubois et al. algorithm. The results obtained using CP are shown to be in good agreement with those obtained from the standard Dubois et al. algorithm using fully polarimetric data. This implies that, for soil moisture, CP can be used instead of HH and VV dual-polarized measurements. [ABSTRACT FROM AUTHOR]

Abstract: This paper is the second in a series revisiting the (effect of) Faraday rotation. We formulate and prove the thermodynamic limit for the transverse electric conductivity of Bloch electrons, as well as for the Verdet constant. The main mathematical tool is a regularized magnetic and geometric perturbation theory combined with elliptic regularity and Agmon–Combes–Thomas uniform exponential decay estimates. [Copyright &y& Elsevier]

A hierarchical metropolitan quantum cryptography network upon the inner-city commercial telecom fiber cables is reported in this paper. The seven-user network contains a four-node backbone net with one node acting as the subnet gateway, a two-user subnet and a single-fiber access link, which is realized by the Faraday-Michelson interferometer set-ups. The techniques of the quantum router, optical switch and trusted relay are assembled here to guarantee the feasibility and expandability of the quantum cryptography network. Five nodes of the network are located in the government departments and the secure keys generated by the quantum key distribution network are utilized to encrypt the instant video, sound, text messages and confidential files transmitting between these bureaus. The whole implementation including the hierarchical quantum cryptographic communication network links and the corresponding application software shows a big step toward the practical user-oriented network with a high security level. [ABSTRACT FROM AUTHOR]

The present paper deals with an analytical study of a self-generated axial magnetic field (SGAMF) through the inverse Faraday effect (IFE) and its influence on the propagation of circularly polarized light wave for relativistic intensities. As a first step, the non-linear dielectric constant incorporating a magnetic field in the relativistic factor within the framework of WKB (for Wentzel, Kramers, and Brillouin) and a paraxial ray theory is formulated. It is noticed that for intensities (>1018 W cm-2), circularly polarized radiation can propagate in electron plasma whose density is greater than the critical density as well as a strong flow of relativistic electrons, axially co-moving with the pulse rise. The above generates a magnetic field up to 100 MG and strongly influences the light propagation. Two modes of propagation exist, namely, extraordinary and ordinary, and critical power for focusing is different for the two modes. The non-linear dielectric tensor, propagation equation, and the self-trapped radius are evaluated incorporating an induced magnetic field. The focusing conditions strongly depend on the power of the beam, strength of the magnetic field as well as on the density of the medium. Numerical calculations are made for a typical set of relativistic laser plasma interaction processes. [ABSTRACT FROM AUTHOR]

Measurement of an internal magnetic field distribution in magnetically confined fusion devices is indispensable for both understanding the plasma physics and controlling plasmas. A polari-interferometer based on the Faraday effect has been used for such a purpose. This paper describes performance evaluations of a part of the polarimeter with photoelastic modulators (PEMs) of the short-wavelength far-infrared (FIR) laser polari-interferometer. The wavelengths of the light source are 57.2 and 47.7 μ m, which are suitable for a high-density operation and large fusion devices. The PEM for the FIR region is newly developed with high-resistive silicon in which absorption of the FIR laser is small. The polarization angle is successfully measured and an angle resolution of 0.01° with a time resolution of 1 ms is achieved. A drift of the baseline of about 0.1° for 1000 s is observed and is found to be caused by changes in the room temperature. [ABSTRACT FROM AUTHOR]

method of designing high performance millimeter wave quasi-optical Faraday rotators (QOFR) is reported in this paper. First, the dielectric and magnetic parameters for the ferrite sample are determined by fitting theoretical curves to the measured data. These fitted parameters are then used in a precise numerical model to predict the rotation angle and insertion loss of the QOFR. Finally, the parameters of the QOFR are optimized according to the requirements of devices. Examples are given showing the performance of the QOFR with an isolation better than 20 dB and an insertion loss less than 0.6 dB from 75 GHz to 95 GHz. [ABSTRACT FROM AUTHOR]

A new device designed by the senior author of the current paper was examined and tested in the Materials Research Laboratory of The Pennsylvania State University. The device consists of an unconventionally driven magnetron whose directional output is conditioned by filters and a tailored horn antenna. Although the origin of the radiation is an ordinary 600 W magnetron, the modified radiation is not contained by either a Faraday cage or by microwave shielding. It interrupts the operation of electronic devices, shutting them off without apparent harm to the circuitry. The radiation was observed to pass through or circumvent a one inch block of aluminium. Lastly, it unexpectedly attenuated in the building ventilation ducts which were completely outside of the directional field, resulting in the heating of and off-gassing from sealant in the duct flanges. [ABSTRACT FROM AUTHOR]

In this manuscript, the values of Faraday rotation for wavelengths between 675 and 875 nm and also Verdet constant (for magnetic field in 15 kOe) of nanocrystal and thin film forms of cadmium manganese telluride have been experimentally measured. The Verdet constant of antimagnetic elements like cadmium telluride is very low, which experimentally measured in this paper. Finally, we observed that in high wavelengths compared with initial state, Verdet constants and values of Faraday rotation have decreases process which we explained it in literature. [ABSTRACT FROM AUTHOR]