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This work presents a highly sensitive hybrid-integrated optical receiver with a custom designed linear transimpedance amplifier (TIA). The choice of the circuit and diode technology, considering the impact of process parameters on the optical sensitivity and the input referred noise current, are elaborated. The TIA has been designed in a 55-nm complementary metal oxide semiconductor process and was combined with a commercial InGaAs/InP PIN-diode. Measurements resulted in a transimpedance of 9.2 kΩ and a bandwidth of 1.4 GHz. The optical sensitivity of the hybrid receiver is −27.45 dBm for 2 Gbps, with a wavelength of 1550 nm and a bit error rate of 10 − 9. The input referred root mean square (RMS) noise current results in 110 nA. The fabricated chip has an area of 410 μm × 410 μm and a power consumption of 31 mW at a 1 V supply voltage. The performance of the designed TIA is able to match other designs used in high sensitivity applications such as continuous variable quantum key distribution or optical wireless communication, while consuming significantly less power and having a smaller chip area. [ABSTRACT FROM AUTHOR]

It has been shown that in the asymptotic case of infinite-key length, the 2-decoy state Quantum Key Distribution (QKD) protocol outperforms the 1-decoy state protocol. Here, we present a finite-key analysis of the 1-decoy method. Interestingly, we find that for practical block sizes of up to 108 bits, the 1-decoy protocol achieves for almost all experimental settings higher secret key rates than the 2-decoy protocol. Since using only one decoy is also easier to implement, we conclude that it is the best choice for QKD, in most common practical scenarios. [ABSTRACT FROM AUTHOR]

To meet energy-efficient performance demands, the computing industry has moved to parallel computer architectures, such as chip multiprocessors (CMPs), internally interconnected via networks-on-chip (NoC) to meet growing communication needs. Achieving scaling performance as core counts increase to the hundreds in future CMPs, however, will require high performance, yet energy-efficient interconnects. Silicon nanophotonics is a promising replacement for electronic on-chip interconnect due to its high bandwidth and low latency, however, prior techniques have required high static power for the laser and ring thermal tuning. We propose a novel nano-photonic NoC (PNoC) architecture, LumiNOC, optimized for high performance and power-efficiency. This paper makes three primary contributions: a novel, nanophotonic architecture which partitions the network into subnets for better efficiency; a purely photonic, in-band, distributed arbitration scheme; and a channel sharing arrangement utilizing the same waveguides and wavelengths for arbitration as data transmission. In a 64-node NoC under synthetic traffic, LumiNOC enjoys 50% lower latency at low loads and \sim40\% higher throughput per Watt on synthetic traffic, versus other reported PNoCs. LumiNOC reduces latencies \sim40\% versus an electrical 2-D mesh NoCs on the PARSEC shared-memory, multithreaded benchmark suite. [ABSTRACT FROM PUBLISHER]

Optical communications and computing require on-chip nonreciprocat light propagation to isolate and stabilize different chip-scale optical components. We have designed and fabricated a metallic-silicon waveguide system in which the optical potential is modulated along the length of the waveguide such that nonreciprocal light propagation is obtained on a silicon photonic chip. Nonreciprocal light transport and one-way photonic mode conversion are demonstrated at the wavelength of 1.55 micrometers in both simulations and experiments. Our system is compatible with conventional complementary metal-oxide-semiconductor processing, providing a way to chip-scale optical isolators for optical communications and computing. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate the active inhibition of subwavelength confined cavity modes emission and quality factor enhancement by controlling the cavity optical surrounding. The intrinsic radiation angular spectrum of modes confined in planar photonics crystal cavities as well as its modifications depending on the environment are inferred via a transfer matrix modeling and κ-space imaging. [ABSTRACT FROM AUTHOR]

We discuss the heat transfer by photons between two metals coupled by a circuit containing linear reactive impedances. Using a simple circuit approach we calculate the spectral power transmitted from one metal to the other and find that it is determined by a photon transmission coefficient which depends on the impedances of the metals and of the coupling circuit. We study the total photonic power flow for different coupling impedances both in the linear regime where the temperature difference between the metals is small and in the nonlinear regime of large temperature differences. [ABSTRACT FROM AUTHOR]

We describe the main recent technological approaches that associate micro-optical elements to VCSELs in order to control their output beam and to improve their photonic integration. These approaches imply either a hybrid assembly or a direct integration technique. They are compared with regards to their tolerance to alignment errors and to their ease of implementation onto arrays of devices at a wafer level. In particular, we detail the integration techniques we have developed for self-aligned polymer microlens fabrication for beam collimation and short distance beam focusing. Finally, designs to achieve active micro-optics or to exploit novel nanophotonic effects are discussed. [ABSTRACT FROM AUTHOR]

A polygonal prism based holographic fabrication method has been demonstrated for a six-layer three-dimensional face-centered-cubic (FCC)-type submicron polymeric photonic crystal using both positive and negative photoresists. Special fabrication treatments have been introduced to insure the survivability of the fabricated large area nano-structures. The SEM results proved the good uniformity of the fabricated structures. With the proper design of the refraction prism we have achieved the required bandgap for S+C band (1460-1565nm) in the [111] direction. The superprism effects around 1550nm wavelength for the fabricated 3D polymer photonic crystal have also been theoretically calculated and such effects can be used for beam steering purpose. [ABSTRACT FROM AUTHOR]

Abstract: We propose a new method for tailoring light structures using a double axicon holographic pattern. The light structure can be tailored using pairs of Bessel modes with different angular momentum indices, and changed into an optical wheel by combining two copropagating Bessel beams. We also demonstrated that the optical wheel obtained from a pair of Bessel beams had rotation feature over the propagation distance by introducing different axial wavenumbers between the two modes. [ABSTRACT FROM AUTHOR]

To avoid the adverse effect of unstable nonlinear progress on the design of all-optical logic gates, the broadband defect mode of one-dimensional photonic crystal with dual-defects has been studied. By using transfer matrix method, influences of period number and refractive indices on crystal's transmission spectrum are analyzed. It is pointed out that with proper parameters, broadband defect mode, which could be used to reduce the influence between the nonlinear refractive index and field distribution, can be gained. Due to this fact, the designed XOR, AND and NOT logic gates can be steadily controlled with low-threshold and high-contrast. [ABSTRACT FROM AUTHOR]

We show theoretically that the frequency range of the zero-averaged refractive-index gap can be substantially extended in a photonic heterostructure containing negative-index materials. This photonic heterostructure consists of different one-dimensional (1D) photonic crystals. The constituent 1D photonic crystals have to be properly chosen in such a way that their zero-averaged refractive-index gap of the adjacent photonic crystals overlap each other. [ABSTRACT FROM AUTHOR]

Sensor systems provide a critical capability for maintaining situational awareness for defense and security applications. Advances in sensor system technology over the last fifty years have created sophisticated systems to collect, detect, process, and respond to radiation over much of the electromagnetic spectrum. In this article, we discuss the physical processes important to the design of photonic sensing, review programs advancing sensor technologies at the Defense Advanced Research Projects Agency, and provide some insight to future capabilities. [ABSTRACT FROM AUTHOR]

Achieving on-chip optical signal isolation is a fundamental difficulty in integrated photonics. The need to overcome this difficulty is becoming increasingly urgent, especially with the emergence of silicon nano-photonics, which promises to create on-chip optical systems at an unprecedented scale of integration. Until now, there have been no techniques that provide complete on-chip signal isolation using materials or processes that are fundamentally compatible with silicon CMOS processes. Based on the effects of photonic transitions, we show here that a linear, broadband and non-reciprocal isolation can be accomplished by spatial–temporal refractive index modulations that simultaneously impart frequency and wavevector shifts during the photonic transition process. We further show that a non-reciprocal effect can be accomplished in dynamically modulated micrometre-scale ring-resonator structures. This work demonstrates that on-chip isolation can be accomplished with dynamic photonic structures in standard material systems that are widely used for integrated optoelectronic applications. [ABSTRACT FROM AUTHOR]

A multiresolution time-domain (MRTD) technique is proposed and applied to the analysis of arbitrarily shaped photonic devices. The suggested method implements the multiresolution analysis in the context of method-of-moments for the solution of Maxwell's equations. To improve the capabilities of the proposed method, the uniaxial perfectly matched layers absorber for the MRTD is rigorously incorporated and better performance is reported over the conventional finite-difference time-domain. Various numerical examples demonstrate the stability and numerical precision of the suggested MRTD method for both linear and nonlinear applications. Moreover, the application of the suggested MRTD scheme for the design of a photonic crystal-based optical wavelength filter and for the analysis of a frequency converter is presented. [ABSTRACT FROM AUTHOR]

A three-party controlled deterministic secure quantum communication scheme through entanglement swapping is proposed firstly. In the scheme, the sender needs to prepare a class of Greenberger–Horne–Zeilinger (GHZ) states which are used as quantum channel. The two communicators may securely communicate under the control of the controller if the quantum channel is safe. The roles of the sender, the receiver, and the controller can be exchanged owing to the symmetry of the quantum channel. Different from other controlled quantum secure communication schemes, the scheme needs lesser additional classical information for transferring secret information. Finally, it is generalized to a multiparty controlled deterministic secure quantum communication scheme. [ABSTRACT FROM AUTHOR]

Abstract: We report the results concerning the theoretical optimization of a surface plasmon-polariton-based waveguide at the optical communication wavelength of 1.55μm. In particular, the effect of metal thickness and grating depth on the excitation of long- and short-range surface plasmon-polaritons in a dielectric/metal/dielectric structure are considered. It is shown that the coupling between these modes increases as the metal thickness decreases with the tendency of modes to overlap when the grating depth and metal thickness are reduced to values of, respectively, 50 and 25nm. Also, the attenuation and confinement in these waveguide structures are inspected theoretically as the thicknesses of the three most used metals (Ag, Au and Al) are varied. The results confirm the established requirement of a trade-off between high confinement and low loss. [Copyright &y& Elsevier]

Abstract: We propose a flexible design for one-dimensional photonic crystals (1D-PCs) with controllable bandgap width which based on the two refractive index mediums. In this structure, each of the low index layers replaced by equivalent three-layers which consist of the same applicable and compatible materials of the basic structure but different fractional optical thicknesses. When decreasing the effective optical contrast ratio of the medium (the ratio of the high refractive to effective refractive index) less than its ordinary value, the relative bandwidth of the 1D-PCs can be changed continuously to any desired value. As an example, for the medium made of TiO2 and SiO2 as the high and low refractive index, and using the concept of symmetric three-layers structure, the results demonstrate that when the effective optical contrast ratio adjusted from 1.61 to less than 1.07, the relative bandwidth of the photonic bandgap (PBG) can be varied continuously (from 0.30 to less than 0.04). [Copyright &y& Elsevier]

Abstract: In this paper the dispersion properties and confinement loss of hollow-core photonic bandgap fibers (PBGFs) based on a square lattice (SL) with rounded square air-holes was investigated for the first time, by using a full-vector finite element method (FEM). The waveguide group velocity dispersion (GVD) curves with different core diameter D, air hole size d, rounded diameter d c and hole pitch Λ are presented. The influence of the number of cladding rings on dispersion and confinement loss were also calculated. It was found that as Λ or d increases, the width of PBG becomes wider, and that D and the number of cladding rings have a smaller influence on waveguide GVD. The ratio between bandgap width and central wavelength in our simulation is about 38.1%, which is larger than that of hollow-core PBGFs with triangular lattice (TL) (∼25%). By simulation, the desired zero dispersion wavelength or desired dispersion slope could be obtained by properly choosing the value of d c or Λ. Compared to TL PBGF, at least nine cladding rings is needed to achieve the confinement loss less than 0.1dB/m for future application. [Copyright &y& Elsevier]

We have proposed a novel scheme to generate optical mm-wave DWDM signals with four time frequency of the local oscillator by using only one external modulator. By incorporating the proper direct current (DC) bias on the external modulator to suppress the first order sideband in central office (CO), and using optical filtering technique to separate the optical mm-wave and optical carrier in the base station, the dense wavelength division multiplexing (DWDM) optical millimeter-wave (mm-wave) signals are generated with four times frequency of the LO signal. We have experimentally demonstrated four-channel DWDM optical mm-wave signal generation with a repetitive frequency up to 40 GHz by 10 GHz LO, and down-stream signal delivery over 20-km fiber with 0.7-dB power penalty. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1152–1155, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23328 [ABSTRACT FROM AUTHOR]

This article presents a miniaturized patch antenna for wireless applications at 2.4 GHz. A conventional microstrip-fed patch antenna is firstly designed to operate close to 10 GHz. Then, the antenna is modified to operate at lower frequency without changing the antenna dimensions. First, the ground plane is replaced with a uniplanar-compact-photonic-band-gap (UC-PBG) structure. Then, a backed conductor is placed close to the UC-PBG and connected to it through four vias. These two modifications are utilized to decrease the lower operating frequency of the antenna from 9.7 to 2.42 GHz. Thus, a 75% size reduction factor is obtained. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1360–1363, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23381 [ABSTRACT FROM AUTHOR]

The micro mechanical model by Gurson–Tvergaard–Needleman is widely used for the prediction of ductile fracture. Some material properties (Gurson parameters) used as material input in this model for simulation are estimated experimentally from specimen level. In this article an attempt has been made to tune the values of some of these Gurson’s parameters by comparing the simulated results with the experimental results in the specimen level (axisymmetric tensile bar and CT specimens). An elastic–plastic finite element code has been developed together with Gurson–Tvergaard–Needleman model for void nucleation and growth. The initial value of f c is determined from Thomason’s limit load model and then tuned on the basis of best prediction of the failure of one-dimensional tensile bar. Then the load versus load line displacement and J versus $${\Updelta}$$ a results for CT specimen are generated with the same code and the value of f n is tuned to match the simulated J versus $$\Updelta$$ a results with the experimental results. Lastly the same code and the Gurson’s parameters obtained are used to simulate the load versus load point displacement and crack growth for pipe with circumferential crack under four point bending. The simulated results are compared with the experimental results to assess the applicability of the whole method. In the proposed material modelling, post-yielding phenomena and necking of the tensile bar are simulated accordingly and strain softening due to void nucleation and growth has been taken care of properly and drop in stress is implicitly simulated through a model. Incremental plasticity theory with arc length method is used for the nonlinear displacement control problem. [ABSTRACT FROM AUTHOR]

Biodegradable inverse opal (IoPPC) was synthesized from a multifunctional carboxylic acid and polyols by colloidal crystal templating. The IoPPC was prepared by infiltration of the monomer solution into interparticle voids of silica colloidal crystal template, polycondensation of the infiltrated film, and removal of the template. The synthesized IoPPC was characterized by infrared absorption, X-ray diffraction measurements, differential scanning calorimetry, and thermogravimetry/mass spectrometry analysis. In order to clarify the effect of biodegradation on the inverse opal structure and the optical reflection property, the IoPPC was implanted in subcutaneous tissue of the lower back of three mice (ICR, 10 weeks, female). After the 2 weeks implantation, fragmented samples were harvested from the implant location and investigated by scanning electron microscope observations and optical reflection measurements. It was found that the reflection peak for the harvested samples decayed from that for the sample without implantation. Such a spectral change is considered to be attributed to the deterioration of the regularity of the inverse opal structures through biodegradation. The finding of this study will serve in the development of reflection-based sensing in various biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract: A kinematic analysis of refraction at the boundary between the (111) surface of a 200nm close-packed fcc-SiO2-based opal and vacuum is presented. The dispersion relation and the equi-frequency surface (EFS) of the photonic band structure are calculated using the plane wave expansion method (PWEM) in order to obtain, in a specific case of polarization, the frequency-dependent relation between the incident and propagation angles. From these refraction properties, one can deduce that the system inhibits the transmission of waves, with frequencies in the visible range, in a wide range of incident angles. [Copyright &y& Elsevier]

We present a systematic analysis of three-dimensionally (3D) ordered photonic crystals fabricated using the recently reported inward growing self-assembling method. The structural and optical characterizations reveal extremely high quality features in these crystals. These include the high reflectance values in the first order stop band and the high energy optical response observed in all the samples, irrespective of the diameter of the spheres, even though the time for fabrication is less than three hours. The photonic stop band is tuned by varying the angle of incidence of light. The peak reflectance and the width of the photonic stop band are unaffected up to an angle of incidence of 45°. At higher angles of incidence, the involvement of other planes in the Bragg reflection is qualitatively demonstrated, emphasizing the extent of ordering and the quality of photonic crystals. [ABSTRACT FROM AUTHOR]

Abstract: We propose a quantum key distribution (QKD) scheme based on entanglement swapping. In this scheme, the methods to form secret keys are so interesting. By comparing initial Bell state and outcome of entanglement swapping, the secret keys between Alice and Bob are generated involuntarily. [Copyright &y& Elsevier]

Abstract: We propose a remote state preparation (RSP) scheme of a three-particle Greenberger–Horne–Zeilinger (GHZ) class state by using three 2-qubit maximally entangled states as the quantum channel. The success probability of preparation and classical communication cost are calculated. Generally speaking, conditioned on Alice’s classical message, with probability 1/4 Bob can successfully prepare the original state by performing one appropriate unitary operation. However, for four kinds of special states, the success probability of preparation can be increased to 1/2 or even 1 after consuming some extra bits. [Copyright &y& Elsevier]

Abstract: To detect and quantify multiple distinct populations of cells circulating simultaneously in the blood of living animals, we developed a novel optical system for two-channel, two-photon flow cytometry in vivo. We used this system to investigate the circulation dynamics in live animals of breast cancer cells with low (MCF-7) and high (MDA-MB-435) metastatic potential, showing for the first time that two different populations of circulating cells can be quantified simultaneously in the vasculature of a single live mouse. We also non-invasively monitored a population of labeled, circulating red blood cells for more than two weeks, demonstrating that this technique can also quantify the dynamics of abundant cells in the vascular system for prolonged periods of time. These data are the first in vivo application of multichannel flow cytometry utilizing two-photon excitation, which will greatly enhance our capability to study circulating cells in cancer and other disease processes. [Copyright &y& Elsevier]

Abstract: We describe the theory of a new method of optical refocusing that is particularly relevant for confocal and multiphoton microscopy systems. This method avoids the spherical aberration that is common to other optical refocusing systems. We show that aberration-free refocusing can be achieved over an axial scan range of 70μm for a 1.4NA objective lens. As refocusing is implemented remotely from the specimen, this method enables high axial scan speeds without mechanical interference between the objective lens and the specimen. [Copyright &y& Elsevier]

Abstract: In this work, the effect of modulation instability (MI) in optical fiber is used to reshape nanosecond pulses form a directly modulated diode laser. Our configuration includes a fiber where MI causes the side lobes in the signal spectrum and a filter at the fiber output rejecting the side lobes. Simulations show abrupt drop of the transmission of the setup if pulse power is above some critical value. We investigated the transmission for fibers with lengths in the range between 62-m and 4.5-km. The critical power was found to be inversely proportional to the fiber length. An average scaled critical power is 2.16Wkm. We demonstrated the application of the method for rejection of the transient peak in a directly modulated diode laser. [Copyright &y& Elsevier]

Abstract: We present a experimental and theoretical investigation of spontaneously initiated stimulated Brillouin scattering in which the interplay of two independent noise sources (thermal and pump) can be studied by controlling the relative importance of each source. We vary the pump noise by adding a controlled amount of Gaussian noise to the input pulses, and we control the contribution of the thermal noise by examining the energy statistics of both entire scattered pulses and of temporal slices of the scattered pulses. We show that the energy of the whole Stokes pulses follow a Gaussian distribution but that the energy of the Stokes pulse slices do not. [Copyright &y& Elsevier]

Abstract: Using Z-scan method with picosecond laser at 532nm, the third order optical nonlinearities of ZnFe2O4 were investigated. The nonlinear refractive index is positive for all ZnFe2O4 samples and decrease with the nanocrystal size. The nonlinear absorption dominated by saturable absorption for 19nm and 11nm ZnFe2O4 but by two photon absorption for 5nm ZnFe2O4 organosol. Origin of the optical nonlinearities and the size effect has been discussed. [Copyright &y& Elsevier]

Abstract: A laser-diode end-pumped acousto-optic (AO) Q-switched Nd:YVO4/KTP red laser by using a plano-concave cavity was demonstrated for the first time. This linear cavity configuration could guarantee not only moderate intracavity focusing on KTP crystal but also good beam quality. Under the absorbed pump power of 14.8W, the maximum average output power at 671nm was obtained to be 1.37W at the repetition frequency of 15kHz, with the corresponding optical conversion efficiency of 9.3% and the pulse width of 33ns. The energy of a single pulse and corresponding peak power are estimated to be 91.3μJ and 2.77kW, respectively. The rate equations are also numerically solved by introducing the nonlinear loss resulting from generation of second-harmonic wave. [Copyright &y& Elsevier]

Abstract: We investigated second harmonic generation (SHG) from neutral and electrically charged water microdroplets of uniform size. We found that angular distribution, polarization, and conversion efficiency of the SHG emission did not change within applied surface charge densities from 0 to 7.2×10−5 C/m2. The latter is consistent with previously observed charge sensitive SHG efficiency on water interfaces if one considers particular experimental conditions. A brief discussion of the applicability of SHG for optical detection of charges in atmospheric clouds is given. [Copyright &y& Elsevier]

Abstract: The unclamped relative permittivity, , and the Pockels coefficient, , of congruent lithium niobate at a frequency f =5760Hz have been determined at low temperatures (7K< T <300K). A He cryostat setup mounted to one arm of an electronically phase-stabilized Michelson interferometer was utilized for the measurement of . A continuous decrease in both parameters was observed as T →0K with limiting values of and , respectively. [Copyright &y& Elsevier]

Abstract: Nonlinear coefficient and group-velocity-dispersion of bismuth-based nonlinear fibers were determined by four-wave-mixing measurements. The wavelength dependence of refractive index of bulk bismuth-based glasses was also measured to estimate the material dispersion and waveguide dispersion. A newly developed bi-directional four-wave-mixing configuration enabled us to determine all fiber parameters simultaneously. The obtained fiber nonlinearity γ ∼1000W−1 km−1 of bismuth-based nonlinear fiber is the highest one in the step-index fiber made of oxide glasses as expected from a high refractive index at 1550nm. Dispersion analysis reveals that the both material dispersion and waveguide dispersion affect to the large group-velocity-dispersion of bismuth-based nonlinear fiber. [Copyright &y& Elsevier]

Abstract: Nonlinear refraction and nonlinear absorption of diphenylporphyrins with bromination and metallization were studied by Z-scan technique in nanosecond and picosecond regimes. Results show that both metallization and bromination of diphenylporphyrins can cause the regular change of magnitude and sign of nonlinear absorption. The transition between saturable absorption and reverse saturable absorption happens as bromine increases and metal ion changes. The effect of bromination on nonlinear refraction is small, the change of nonlinear refraction is mainly attributed to the metallization. Influences of photophysical parameters on nonlinear absorption and nonlinear refraction have been elucidated using five-level models. [Copyright &y& Elsevier]

Abstract: We report a simple method to realize all-optical dual-direction half-subtracter at 40Gb/s based on sum-frequency generation (SFG) using only one periodically poled lithium niobate (PPLN) waveguide. The SFG process generates the Borrow outputs and the combination of the outputs from PPLN after SFG results in the Difference. The operation performance of the proposed scheme is simulated, including eye diagrams, Q-factor, extinction ratio, and tunability. For different input optical powers, the length of the PPLN waveguide is optimized. [Copyright &y& Elsevier]

Abstract: We report the group delay dispersion of Yb3+:YAl3(BO3)4 (Yb:YAB) crystal measured by a white-light interferometer, and compare with that calculated from the Sellmeier formulae provided by the crystal supplier, over the wavelength range from 1000nm to 1080nm. The data should be useful for the dispersion compensation for femtosecond pulse generation in Yb:YAB lasers. [Copyright &y& Elsevier]

Abstract: We performed two-color spectroscopy of the (4s2) 1S0 →(4s4p) 1P1 →(4p2) 1D2 calcium atomic transition and observed velocity-selective optical pumping in a calcium hollow cathode lamp by means of optogalvanic detection. The optical pumping signature in optogalvanic detection is compared to that of fluorescence and transmission detections. The optogalvanic technique is found to be a very sensitive method of detecting optical pumping and could be used in distinguishing optical pumping from electromagnetically induced transparency. [Copyright &y& Elsevier]

Abstract: In this paper, processing methods of Fourier optics implemented in a digital holographic microscopy system are presented. The proposed methodology is based on the possibility of the digital holography in carrying out the whole reconstruction of the recorded wave front and consequently, the determination of the phase and intensity distribution in any arbitrary plane located between the object and the recording plane. In this way, in digital holographic microscopy the field produced by the objective lens can be reconstructed along its propagation, allowing the reconstruction of the back focal plane of the lens, so that the complex amplitudes of the Fraunhofer diffraction, or equivalently the Fourier transform, of the light distribution across the object can be known. The manipulation of Fourier transform plane makes possible the design of digital methods of optical processing and image analysis. The proposed method has a great practical utility and represents a powerful tool in image analysis and data processing. The theoretical aspects of the method are presented, and its validity has been demonstrated using computer generated holograms and images simulations of microscopic objects. [Copyright &y& Elsevier]

Abstract: It is known that speckle patterns with fractal properties, called fractal speckles, are produced by illuminating a diffuser with the coherent light having the intensity distribution obeying a negative power law. One of key properties of fractal speckles is the spatial correlation function obeying a negative power law, which implies that such speckles have scaling properties. In detecting fractal speckles, the effect of the spatial integration is inevitable in most cases since they have speckle grains of various scales including very fine ones. To evaluate this effect, in this paper, the contrast of spatially integrated intensity distributions is investigated theoretically and experimentally for fractal speckles. The results show that the contrast reduction with the size of the detector aperture obeys a negative power function related with the exponent of the intensity correlation coefficient of fractal speckles. [Copyright &y& Elsevier]

Abstract: The polarization-sensitive propagation in the anisotropic metamaterial (AMM) with double-sheeted hyperboloid dispersion relation is investigated from a purely wave propagation point of view. We show that TE and TM polarized waves present significantly different characteristics which depend on the polarization. The omnidirectional total reflection and oblique total transmission can occur in the interface associated with the AMM. If appropriate conditions are satisfied, one polarized wave exhibits the total refraction, while the other presents the total reflection. We find that the opposite amphoteric refractions can be realized by rotating the principle axis of AMM, such that one polarized wave performs the negative refraction, while the other undergoes positive refraction. The polarization-sensitive characteristics allow us to construct two types of efficient polarizing beam splitters under certain achievable conditions. [Copyright &y& Elsevier]

The combination of quantum teleportation and quantum memory of photonic qubits is essential for future implementations of large-scale quantum communication and measurement-based quantum computation. Both steps have been achieved separately in many proof-of-principle experiments, but the demonstration of memory-built-in teleportation of photonic qubits remains an experimental challenge. Here, we demonstrate teleportation between photonic (flying) and atomic (stationary) qubits. In our experiment, an unknown polarization state of a single photon is teleported over 7 m onto a remote atomic qubit that also serves as a quantum memory. The teleported state can be stored and successfully read out for up to 8 μs. Besides being of fundamental interest, teleportation between photonic and atomic qubits with the direct inclusion of a readable quantum memory represents a step towards an efficient and scalable quantum network. [ABSTRACT FROM AUTHOR]