Matrix approach for modeling of emission from multilayer spin-polarized light-emitting diodes and lasers

Spin-polarized light sources such as the spin-polarized light-emitting diodes (spin-LEDs) and spin-polarized lasers (spin-lasers) are prospective devices in which the radiative recombination of spin-polarized carriers results in emission of circularly polarized photons. The main goal of this article is to model emitted radiation and its polarization properties from spin-LED and spin-controlled vertical-cavity surface-emitting laser (spin-VCSEL) solid-state structures. A novel approach based on 4 × 4 transfer matrix formalism is derived for modeling of the interaction of light with matter in active media of resonant multilayer anisotropic structure and enables magneto-optical effects. Quantum transitions, which result in photon emission, are described using general Jones source vectors.Web of Science166art. no. 06500

Coupled mode enhanced giant magnetoplasmonics transverse Kerr effect

We show that the enhancement of the transverse magneto-optical Kerr effect of a smooth magnetic dielectric film covered by a noble metal grating, is strongly dependent on the precise geometry of this grating. Up till now this magnetoplasmonic enhancement was solely attributed to a nonreciprocal shift of the dispersion of the surface plasmon polariton resonances at the interface with the magnetized substrate. It is demonstrated that by hybridization of surface and cavity resonances in this 1D plasmonic grating, the transverse Kerr effect can be further enhanced, extinguished or even switched in sign and that without inverting or modifying the film’s magnetization. This strong geometrical dispersion and the accompanying anomalous sign change of the magneto-plasmonic effects in such systems has never been considered before, and might find interesting applications in sensing and nanophotonics.Web of Science2119217552174

Theoretical and experimental study of plasmonic effects in heavily doped gallium arsenide and indium phosphide

Dispersion plasmonic interaction at an interface between a doped semiconductor and a dielectric is employed to use experimental data for determining the plasma frequency, the relaxation time, the effective mass, and the mobility of free electrons in heavily donor-doped gallium arsenide (GaAs) and indium phosphide (InP). A new solution for a plasmonic resonance at a semiconductor/dielectric interface found recently is exploited advantageously when analyzing the experimental data. Two independent measurement methods were used, namely the infrared reflectivity and the Raman scattering. Results indicate a good agreement with known data while pointing to some inaccuracies reported, and suggest a new alternative and accurate means to determine these important semiconductor parameters.Web of Science5235234

Plasmonic behavior of III-V semiconductors in far-infrared and terahertz range

Background: In this article, III-V semiconductors are proposed as materials for far-infrared and terahertz plasmonic applications. We suggest criteria to estimate appropriate spectral range for each material including tuning by fine doping and magnetic field. Methods: Several single-crystal wafer samples (n, p-doped GaAs, n-doped InP, and n, p-doped and undoped InSb) are characterized using reflectivity measurement and their optical properties are described using the Drude-Lorentz model, including magneto-optical anisotropy. Results: The optical parameters of III-V semiconductors are presented. Moreover, strong magnetic modulation of permittivity was demonstrated on the undoped InSb crystal wafer in the terahertz spectral range. Description of this effect is presented and the obtained parameters are compared with a Hall effect measurement. Conclusion: Analyzing the phonon/free carrier contribution to the permittivity of the samples shows their possible use as plasmonic materials; the surface plasmon properties of semiconductors in the THz range resemble those of noble metals in the visible and near infrared range and their properties are tunable by either doping or magnetic field.Web of Science13art. no. 1

High-resolution THz gain measurements in optically pumped ammonia

This study is aimed at the evaluation of THz gain properties in an optically pumped NH3 gas. NH3 molecules undergo rotational-vibrational excitation by mid-infrared (MIR) optical pumping provided by a MIR quantum cascade laser (QCL) which enables precise tuning to the NH3 infrared transition around 10.3 mu m. Pure inversion transitions, (J = 3, K = 3) at 1.073 THz and (J = 4, K = 4) at 1.083 THz were selected. The THz measurements were performed using a THz frequency multiplier chain. The results show line profiles with and without optical pumping at different NH3 pressures, and with different MIR tuning. The highest gain at room temperature under the best conditions obtained during single pass on the (3,3) line was 10.1 dBxm(-1) at 26 mu bar with a pumping power of 40 mW. The (4,4) line showed lower gain of 6.4 dBxm(-1) at 34 mu bar with a pumping power of 62 mW. To our knowledge these THz gains are the highest measured in a continuous-wave MIR pumped gas.Web of Science2616212482124

Mueller matrix optical and magneto-optical characterization of Bi-substituted gadolinium iron garnet for application in magnetoplasmonic structures

A ferromagnetic garnet, used as a magneto-optical (MO) material in magneto-photonic and magneto-plasmonic structures, is characterized. We present a general procedure to determine optical and magneto-optical functions of the magneto-optic garnet by using Mueller matrix ellipsometry. In the first step, the optical functions (the refractive index spectra) of the (CaMgZr)-doped gallium-gadolinium garnet (sGGG) substrate and the Bi-substituted gadolinium iron garnet Gd1.24Pr0.48Bi1.01Lu0.27Fe4.38Al0.6O12 (Bi:GIG) are obtained in the spectral range from 0.73 eV to 6.42 eV (wavelength range 193 nm – 1.7 μm). Subsequently, the spectra of the magneto-optical tensor components are obtained by applying an external in-plane magnetic field in longitudinal and transverse geometry. The obtained functions are then used to fit the Mueller matrix spectra of a magneto-plasmonic structure with a gold grating on the magneto-optic garnet layer. This structure has recently been demonstrated to have strongly enhanced transverse magneto-optic Kerr response at visible and near-infrared frequencies. By taking possible fabrication imperfections (surface roughness, residual photo-resist layer, thickness deviation) into account, the measured strongly enhanced MO response fits very well to the numerical model predicting these exaltations.Web of Science491919190

Magneto-optical properties of InSb for terahertz applications

Magneto-optical permittivity tensor spectra of undoped InSb, n-doped and p-doped InSb crystals were determined using the terahertz time-domain spectroscopy (THz-TDS) and the Fourier transform far-infrared spectroscopy (far-FTIR). A Huge polar magneto-optical (MO) Kerr-effect (up to 20 degrees in rotation) and a simultaneous plasmonic behavior observed at low magnetic field (0.4 T) and room temperature are promising for terahertz nonreciprocal applications. We demonstrate the possibility of adjusting the the spectral rage with huge MO by increase in n-doping of InSb. Spectral response is modeled using generalized magneto-optical Drude-Lorentz theory, giving us precise values of free carrier mobility, density and effective mass consistent with electric Hall effect measurement.Web of Science611art. no. 11502

Effects of optical activity to Mueller matrix ellipsometry of composed waveplates

Mueller matrix ellipsometry has been used to precisely characterize quartz waveplates for demanding applications in the semiconductor industry and high precision polarimetry. We have found this experimental technique to be beneficial to use because it enables us to obtain absolute and precise measurement of retardation in a wide spectral range, waveplate orientation, and compound waveplate adjustment. In this paper, the necessity of including the optical activity in the Mueller matrix model and data treatment is demonstrated. Particularly, the optical activity of the quartz influences the adjustment of misalignment between the perpendicularly oriented waveplates of the compound biplate. We demonstrate that omitting the optical activity from the model leads to inaccurate values of the misalignment. In addition, the depolarization effects caused by a finite monochromator bandwidth is included in the model. Incorporation of the optical activity to the Mueller matrix model has required a development of rigorous theory based on appropriate constitutive equations. The generalized Yeh's matrix algebra to bianisotropic media has been used for the calculation of the eigenmodes propagation in chiral materials with reduced symmetry. Based on the applied method, the authors have proposed approximated analytical form of the Mueller matrix representing optically active waveplate and biplate and provided discussion on the analytical and numerical limits of the method.Web of Science297104501043