A continuously tunable long-wavelength cw IR source for high-resolution spectroscopy and trace-gas detection

A new widely tunable source in the infrared for use in high-resolution spectroscopy and trace-gas detection is described. This spectroscopic source is based on Difference Frequency Generation (DFG) in gallium selenide (GaSe) and is continuously tunable in the 8.8–15.0 m wavelength region. Such a DFG source operates at room temperature which makes it a useful alternative to a lead-salt diode-laser- based detection system that requires cryogenic temperatures and numerous individual diode lasers.Prof. F. P. Schäfer on the occasion of his 65th birthday.     

Interaction of long-wavelength excitations in crystals

The conditions of resonance interaction of phonons for a scalar model of a crystal in the region of the initial linear section of the dispersion curve of acoustic phonons are investigated using two-particle Green's functions. Fiz. Tverd. Tela (St. Petersburg) 41, 130–133 (January 1999)     

Study of birefringence in porous silicon layers by IR Fourier spectroscopy

Birefringence in porous silicon layers prepared with different etching currents on a (110) substrate is studied by IR Fourier spectroscopy. The spectra exhibit beats in the intensity of transmitted and reflected radiation due to the summation of the intensities of the ordinary and extraordinary waves interfering in the porous layer. An analysis of the spectra shows the layers to exhibit properties of a negative uniaxial crystal with the optical axis lying in the layer plane. The difference between the refractive indices of the ordinary and extraordinary waves for a layer with a porosity of 80% reaches 18%. The experimental data are in agreement with the calculations based on the effective-medium approximation, which takes into account the anisotropy of silicon nanocrystal arrangement in a porous layer.     

Study of trimethylsilylated aerosil by IR and29Si NMR spectroscopy

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 56, No. 3, pp. 364–367, March, 1992.     

壳聚糖与不同金属锌盐配位的红外光谱研究

用壳聚糖和硫酸锌合成了一系列不同配比的配合物。通过对这些配合物红外光谱的分析和比较,考察了主要吸收峰随不同配比的变化规律,照发了它们的主要红外吸收峰,研究还表明,不同锌盐与壳聚糖形成的配合物有不同的配位环境。     

Study of polycomplexes based on lignosulfonates and urea-formaldehyde resins by IR spectroscopy

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 48, No. 1, pp. 95–98, January, 1988.     

邻苯二甲酸二甲酯晶体中裂纹愈合效应的力学谱研究

推广应用应力诱导裂纹和裂纹愈合的新方法（RMS-CH方法,Wu等,Appl. Phys. Lett. 92 011918-1（2008））于晶体材料的应力诱导裂纹和裂纹愈合过程的实时检测.对邻苯二甲酸二甲酯晶体的测量结果表明,在定升温速率条件下：1）裂纹愈合的速率随温度变化表现为较为尖锐的单峰,对应的峰温可以作为裂纹愈合的特征温度T^c_ch,且T^c_ch=206 K;2）裂纹愈合速率峰是不对称的 关键词： 裂纹愈合 晶体缺陷 力学谱     

Diffraction of IR radiation by ultrasound in tellurium single crystals

The optic, acoustic, and acousto-optic properties of tellurium single crystals are considered to analyze the possibilities of applying this material in acousto-optic filters to control mid- and far-IR radiation. The results of measuring the optic and acousto-optic parameters of a tellurium crystal are reported. The isotropic and anisotropic light diffraction by ultrasound in the crystal is investigated. The wide-aperture geometry of interaction in tellurium is implemented and an acousto-optic figure of merit M ₂ of a tellurium crystal exceeding 10 × 10^?15 s³ g^?1 is experimentally obtained.     

Study of iron implanted MgO crystals by low-energy electron induced X-ray spectroscopy

Magnesium oxide crystals implanted with Fe⁺ ions have been studied by means of Low-Energy-Electron-Induced X-ray Spectroscopy. All the implantations were carried out with 100 or 150 keV ion energy, at doses in the range from 10¹⁵ to 10¹⁷ ions cm^?2. The structure of the Fe L_II, L_III X-ray emission bands provides information about the iron chemical state. Fe L_II/L_III band intensity ratio measurements have been performed with a 3 keV electron excitation in order to investigate the whole implanted layer. In addition, by using a filtered Fourier transform technique on observed spectra, some modifications in the oxygen K emission band can be observed in implanted MgO crystals after thermal annealings in air. The oxygen spectrum fine structure suggests that the MgO matrix, partially destroyed by iron implantation, is restored after high temperature treatments. All the implantation, is restored after high temperature treatments. All the results are discussed on the basis of previous Mössbauer Spectroscopy studies and ion channeling investigations.     

Upconversion of IR radiation into the visible and UV ranges

A review of theoretical and experimental results on the upconversion of IR radiation due to resonant nonlinear phenomena in metal vapors is presented. Various experimental schematics providing high quantum conversion efficiency and the feasibility of converting an arbitrary IR wavelength are discussed.     

Time-resolved IR spectroscopy of quantum-optics in semiconductors

Time-resolved IR spectroscopy is a powerful non-destructive technique for probing electron dynamics and plasmonics in semiconductors. We present recent experiments in which intense IR laser pulses are used to induce “quantum-optical” phenomena, including gain without population inversion and slow light, in semiconductor nanostructures. The potential advantages of IR Synchrotron radiation to probe these systems are discussed.     

Device for measuring doping impurities of Groups III and V in high-purity silicon by long-wavelength spectroscopy

An experimental installation for analyzing electrically active impurities in high-purity silicon by investigating low-temperature transmission spectra withcompensation for donor-acceptor impurities is fabricated. The applicability of the method for studying both high-purity and doped silicon wafers is shown.Software for automatically computing the concentration of impurities is developed.