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A new optical setup is described that allows the reflectivity at grazing incidence to be measured, including ultrathin films and two-dimensional electron systems (2DES) down to liquid-helium temperatures, by exploiting the Berreman effect and the high brilliance of infrared synchrotron radiation. This apparatus is well adapted to detect the absorption of a 2DES of nanometric thickness, namely that which forms spontaneously at the interface between a thin film of LaAlO3 and its SrTiO3 substrate, and to determine its Drude parameters.

By use of resonantly-enhanced mechanical photoexpansion technique we have performed mid-infrared vibrational spectroscopy and imaging on the nanoscale of individual purple membranes deposited on ultraflat gold substrate. The observed Amide I and Amide II bands of proteins are in good agreement with the far-field infrared transmission spectra previously collected on large numbers of membranes. A comparison between the near-field signal of single purple membranes and that of two overlapping membranes is presented. The results are discussed by adopting simple thermal and electromagnetic considerations.

We report on the electromagnetic response in metamaterials constituted by 2-dimensional array of metallic elements. The metamaterial transmittance presents a single dipolar resonance which can be easily shifted in the spectral region from 1 to 5 THz through the invariance properties of Maxwell equations under a scale transformation. Basing on these studies, we have designed and tested both direct (bandstop) and complementary (bandpass) filters fabricated by electron beam lithography, investigating the behavior of their figures of merit under the scale transformation. (C) 2010 Elsevier B.V. All rights reserved.

First results from the SINBAD beam line at DAΦNE are reported. The SR brilliance, as measured in the far infrared at the sample position, has been compared with the one of the mercury lamp. For λ =100 μm and through an aperture of 1 mm, the gain in intensity is larger than 20. The high brilliance of the synchrotron radiation in the far-infrared is fully exploited by high-pressure experiments. Preliminary experiments with a diamond-anvil cell in the 10 GPa range are reported.

The infrared synchrotron radiation emitted from a bending magnet of the third generation storage ring ELETTRA is studied in detail by ray-tracing techniques. Constant magnetic-field and edge infrared emissions are taken into account in the project of the bending vacuum chamber and on the beamline design. Moreover the gain in flux and brightness with respect to a conventional source of the infrared radiation are calculated and discussed.

The optical reflectivity in the far infrared region (FIR spectra) was measured for five samples of ZnxCd1−xTe in the Zn range 0.056

The synchrotron radiation emitted in the infrared range from a bending magnet of the third generation storage ring ELETTRA is studied in detail by simulation techniques. Edge effects are taken into account. Preliminary experimental checks on an existing port for beam diagnostics are reported. The design of the infrared beamline under construction, including an evaluation of the tolerance on mirror parameters and of thermal distortions, is presented. Finally, the gain in flux and brightness with respect to a conventional source and the polarization degree of the infrared radiation are calculated and discussed.

The intrinsic linewidth of Surface Plasmon Polariton resonance in a micrometric metal mesh has been measured with a collimated mid-infrared beam, provided by an External-Cavity, tunable Quantum Cascade Laser. The use of a collimated beam yields a resonance linewidth of 12 cm-1, much narrower than by conventional black-body sources. This opens more favorable perspectives to the use of metal meshes as sensors and detectors.

The intrinsic linewidth and angular dispersion of Surface Plasmon Polariton resonance of a micrometric metal mesh have been measured with a collimated mid-infrared beam, provided by an External Cavity tunable Quantum Cascade Laser. We show that the use of a collimated beam yields an observed resonance linewidth γ = 12 cm(-1) at the resonance frequency ν0 = 1658 cm(-1), better by an order of magnitude than with a non-collimated beam. The extremely narrow plasmon resonance attained by our mesh is then exploited to reconstruct, by varying the QCL angle of incidence θ, the angular intensity distribution f(θ) of a globar at the focal plane of a conventional imaging setup. We thus show that f(θ) is better reproduced by a Gaussian distribution than by a uniform one, in agreement with ray-tracing simulation.

We report on the approach to extract the infrared and submillimeter radiation out of insertion devices of synchrotron source. In contrast with conventional schemes of extracting large solid angles from a dipole magnet, at the infrared facility in Orsay (SIRLOIN) we realised a design which minimises the heating of the optics and offers advantages including improved stability of the source. Because of the increased brilliance of future synchrotron facilities, these attributes will be required as the important heat load on optics would force out the conventional method of extraction. The performances of SIRLOIN in the infrared and submillimeter domain will be reviewed and some infrared optical experiments will be summarised. In particular, we will discuss: I) investigations of the infrared reflectivity of microcrystals of High-Tc superconductors. II) Vibrational spectroscopy of small clusters trapped in Argon matrices. III) Reconstruction of gold surfaces at the electrochemical interface.

Two beamlines for the use of InfraRed Synchrotron Radiation (IRSR) are presently working in Italy, at the ELETTRA storage ring in Trieste, and at the collider DAFNE in Frascati. A third facility, SPARC in Frascati, has been equipped for the extraction of Terahertz radiation with the aim to perform pump-probe time-domain experiments. Here we describe those apparata and we review the main results that the Italian groups have obtained therein, in recent years, in solid-state physics. We also describe the experiments performed in collaboration with the storage ring BESSY in Berlin, for the exploitation of Coherent Synchrotron Radiation, and the terahertz beam line recently implemented at SPARC, the Free Electron Laser of Laboratori Nazionali di Frascati

The Q 1 (0) and Q 1 (0)+S 0 (0) infrared bands have been studied in liquid and solid para-H 2 with particular regard to their translational sidebands. In the liquid, their line shapes are well fitted by a model in which the excited particle is encapsulated. In the solid, the phonon sidebands reproduce the main features of the density of states (DOS), as extracted from neutron scattering. The S 1 (0)+S 0 (0) band shows a pure rotonic line shape which is well described by recent DOS calculations

The reflectivity of a large LuFe2O4 single crystal has been measured with the radiation field either perpendicular or parallel to the c axis of its rhombohedral structure, from 10 to 500 K, and from 7 to 16 000 cm(-1). The transition between the two-dimensional and the three-dimensional charge order at T-CO=320 K is found to change dramatically the phonon spectrum in both polarizations. The number of the observed modes above and below T-CO, according to a factor-group analysis, is in good agreement with a transition from the rhombohedral space group R (3) over barm to the monoclinic C2/m. In the subterahertz region a peak becomes evident at low temperature, whose origin is discussed in relation with previous experiments.

We present the design, fabrication and experimental tedt of terahertz bandpass filters made of two-dimensional arrays of Al slot dipoles on Si substrate. The filters are obtained through an inexpensive process with full freedom of design and can be easily implemented for applications in THz spectroscopy.

Infrared spectroscopy and spectromicroscopy have rapidly flourished using the advantages of InfraRed Synchrotron Radiation (IRSR), namely high brightness, broadband emission, linear and circular polarization and pulsed structure. InfraRed (IR) beamlines constructed at all synchrotron facilities provide a unique opportunity for a new class of experiments with significant multidisciplinary impact inaccessible to experimental equipment employing black body (globar) sources.

Summary form only given. This paper presents DAΦNE the electron-positron collider of Laboratori Nazionali di Frascati INFN (Italy), which is operating as a Φ-meson factory for experiments of high energy physics. The high current and low energy of the DAΦNE beam are favourable for extracting infrared synchrotron radiation (IRSR) from bending magnets. SINBAD, the synchrotron infrared beamline at DAΦNE includes an infrared microscope working between 350 and 10000 cm/sup -1/ which is currently employed for the infrared mapping of inhomogeneous solid samples.

This study reviews the various mechanisms exploited to produce infrared synchrotron radiation (IRSR). It shows that at long wavelengths (long when compared to the critical wavelength of the bending magnet in an electron storage ring), the radiation emitted from a bending magnet edge can be brighter than standard synchrotron radiation. For this purpose, we will discuss the various IRSR sources, namely the bending magnets, the wigglers, the undulator and the bending magnet edges. We will then briefly review a high-resolution study of isolated molecules in the far infrared, the detection of a very narrow Drude term in a high- T c superconductor, a description of ultra-high pressure experiments, an investigation of water encapsulated in non-ionic reverse micelles, and finally, a brief review of spatially resolved studies.

Both the angular and the spectral distribution of the Infrared Synchrotron Radiation emitted by an undulator of Super-ACO have been measured. Structures due to undulator edges, as well as contributions from the edge emission of a bending magnet placed behind the undulator, have been observed. Detailed calculations including all these sources are in excellent agreement with the measurements, provided that both velocity and acceleration terms are considered.

SINBAD, the infrared beamline which extracts radiation from the DA(Phi) NE collider of the Laboratori Nazionali di Frascati, will be operating in the fall of 1999. The optical layout of SINBAD, fully designed by ray tracing simulation, includes six mirrors which transfer and focus the radiation to an interferometer placed more than 20 m from the source. The actual brilliance gain at the entrance of the interferometer has been accurately evaluated by simulating the expected aberrations, the mirror roughness, and diffraction effects.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

SINBAD, the first beamline in Italy designed to work in the far- and mid-infrared region, is being installed on DAΦNE storage ring, the new Φ-factory atLaboratoriNazionali di Frascati. DAΦNE, first injected in September 1997, will work at 0.51 GeV with a beam current in the range 2–5 A. The infrared synchrotron radiation extracted from a bending magnet is expected to be more brilliant than a black body at 2000 K up to three orders of magnitude in the wavelength range 10–1000 µm. The optical layout of SINBAD, fully designed by ray tracing simulation, includes six mirrors placed in a 18 m long beamline. The infrared radiation is first focused on a wedged diamond window and then re-focused on the entrance of aMichelson interferometer. Diffraction effects and mirror roughness, as well as optical aberrations, have been evaluated.

Accurate measurements of the translational band were recently performed in the far infrared region on low density He-Xe mixtures. Accurate values of intensity and range of the overlap induced dipole were obtained. A new analysis based on exact quantum line shape computations shows that a term representing the effect of dispersion must be included in the induced dipole, in order to obtain a translational profile which is consistent with the experimental one.

We report on the status of the first Italian Infrared Synchrotron Radiation Beamline SINBAD (Synchrotron INfrared Beamline At DA(Phi) NE), that has been designed to work at wavelengths greater than 10 micrometers . SINBAD is being installed on DA(Phi) NE, the new collider of the Laboratori Nazionali di Frascati designed to work at 0.51 GeV with a beam current of 2 to 5 A. The infrared radiation extracted from a bending magnet under an angle of 50 X 50 mrad will be two orders of magnitude more brilliant than that of a black body at 2000 K at a wavelength of 100 micrometers . The beamline layout, which consists of two planar mirrors, two toroidal mirrors and one aspherical mirror, has been designed by ray tracing simulation. In this layout one ellipsoid focuses the radiation on a wedged CVD diamond-film window, the beam is then re-focused again on the entrance of an interferometer. With a calculated transmittance of the optics between 60% and 80% at 50 micrometers , this beamline will allow experiments which require a very high brilliance in the far infrared.

The actual source area of a bending magnet emitting in the infrared range, has been calculated for the double annular Φ‐factory for nice experiments (DAΦNE) under construction at Frascati. ‘‘Geometrical’’ broadening has been included. The actual brilliance ratio defined as the ratio between the brilliance of a synchrotron source and that of a blackbody, has been also evaluated for DAΦNE and compared with the Brookhaven NSLS source.

The interest for Terahertz (THz) radiation is rapidly growing, both as it is a powerful tool for investigating the behavior of matter at low energy, and as it allows for a number of possible spectroscopic applications spanning from medical science to security. The linac-driven THz source at the SPARC facility can deliver broadband THz pulses with femtosecond shaping and can be used for electron beam diagnostics to fully reconstruct the longitudinal charge distribution. Beyond this application, the possibility to store much more energy in a single THz pulse than table-top sources renders the SPARC THz source very interesting for a spectroscopic use. In addition, taking advantage from electron beam manipulation techniques, high power, narrow-band THz radiation can be also generated. Those source characteristics provide a unique chance to realize THz-pump/THz-probe spectroscopy, a technique practically unexplored up to now.

SINBAD (Synchrotron Infrared Beamline At DAphiNE) is the first Italian synchrotron radiation beamline operating in the infrared range. It collects the radiation emitted by DANE, an electron-positron collider designed to work at 0.51 GeV with a beam current I1 A. The actual performances of the beamline, in terms of brilliance gain with respect to blackbodies and polarization properties, are presented and discussed. Finally, the stability of the SINBAD source, a critical issue for Fourier-transform infrared spectroscopy, is discussed.

Low-resolution transmittance and reflectance spectra of high-quality chemical-vapor deposition (CVD) diamond windows were measured in the infrared in the 2.5-500-mum wavelength range (20-4000 cm(-1)). High-resolution measurements on a window with nearly parallel surfaces show well defined interference fringes at low frequencies. By standard procedures the optical constants n and k of CVD diamond were determined, for the first time to the author's knowledge, in the far-infrared region. It is shown that a window with a large wedge angle, close to 1 degrees , does not produce appreciable interference fringes. Modeling of these results confirms that interference fringes can be avoided by use of properly wedged CVD diamond windows. This result is of considerable relevance to the use of CVD diamond windows in spectroscopic applications for which fringe suppression is a major requirement.

Different optical layouts for a beamline that extracts infrared synchrotron radiation from a bending magnet are discussed, and their performances are compared by use of ray‐tracing simulations. Specific results are presented for SINBAD, the beamline to be mounted on the new Frascati collider DAΦNE.

Measurements of the transmittance of infrared radiation (v

A new mechanism for the emission of infrared synchrotron radiation (IRSR) is observed following the longitudinal acceleration or deceleration of relativistic particles when leaving or entering a magnetic field (edges of dipole or undulator). This emission may present significant advantages in terms of brilliance and intensity compared to the emission by constant field acceleration (center of the magnet). A full numerical integration of the electrodynamic fields have allowed a complete review of the main characteristics of two sources of the 0.8 GeV ring Super-ACO (Orsay, France): a dipole edge and an undulator. The intensity of the emission (flux), brilliance, spatial distribution (asymmetry of the source), dependence of the emission on the magnetic field and polarisation have been evaluated for the emission in the infrared range. These parameters are compared with equivalent measurements providing a confirmation of the theoretical predictions.

Strong emission of highly collimated infrared radiation demonstrates the presence of dipole edge emission and transient undulator radiation emission. The photon flux and spatial distribution for the Super-ACO sources (both dipole edge and wiggler) including coherence effects have been evaluated using the exact expression for the emission of a charged particle. The excellent agreement between these results and measurements performed at the SIRLOIN (Spectroscopie en Infrarouge LOINtain) beam line provides a new level of understanding of infrared synchrotron radiation.

DAΦNE, the new storage ring under construction at Frascati, can also be used as a powerful synchrotron radiation source in the infrared domain, where it is much more brilliant than a blackbody. Ray-tracing calculations of different optical setups at different wavelengths are reported.

The first measurements of the spectral distribution of infrared radiation emitted by an undulator are reported. They are compared with calculations including both velocity and acceleration terms. Measurements have been performed at the beam line SIRLOIN (Spectroscopie en InfraRouge Lointain). The agreement between the observations and this first exact numerical solution shows that the inclusion of the velocity term in the submillimeter frequency range is necessary. Moreover, structures due to undulator edges are observed in the far infrared and mid-infrared range, while the interference pattern due to redshifted harmonics of the undulator is dominating in the mid-infrared to near infrared.