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Infrared absorption and luminescence measurements of substitutional Cr2+(d4) in the II-VI compounds ZnS, ZnSe, ZnTe and CdTe are reported. The experimental results are interpreted in the framework of crystal field theory with spin-orbit coupling and a substantial Jahn-Teller interaction in the 5T2 ground state and a much smaller, but significant, Jahn-Teller interaction in the excited 5E state. With a semiclassical model and a Monte Carlo computing technique convoluted shapes of absorption and luminescence spectra are obtained. The Jahn-Teller energy for the 5T2 ground state is found to be approximately 350 cm-1. For the first time a Jahn-Teller energy for the excited 5E state is reported, and has a value of approximately 50 cm-1. The inclusion of ligand field effects in the spin-orbit coupling constant was found to be important.

Articles you may be interested inOptical and magnetoresistive properties of polycrystalline La0.7Sr0.3MnO3 films on crystalline Al2O3 and Gd3Ga5O12 substrates Low Temp. Phys. 40, 756 (2014); 10.1063/1.4894318 Direct observation of magnetization reversal and low field magnetoresistance of epitaxial La0.7Sr0.3MnO3/SrTiO3 (001) thin films at room temperature Domain nucleation and growth of La 0.7 Ca 0.3 MnO 3−δ /LaAlO 3 films studied by low temperature magnetic force microscopy J. Appl. Phys. 93, 8319 (2003); 10.1063/1.1555315 Perpendicular magnetic anisotropy and magnetic domain structure in sputtered epitaxial FePt (001) L1 0 filmsWe report the magneto-optical ͑MO͒ properties of compressively strained La 0.7 Sr 0.3 MnO 3 ͑LSMO͒ thin films epitaxially grown on a LaAlO 3 substrate. The magnetic force microscope images show the stripe magnetic domains, characteristic of films with the perpendicular magnetic anisotropy ͑PMA͒. The optical reflectance and transmittance of the samples were measured over a broad energy range from the far infrared through the ultraviolet. To extract the optical constants of the films, we analyzed all of the layers of this thin-film structure using a Drude-Lorentz model. From the parameters obtained, we compute the optical constants, such as frequency-dependent optical conductivity and the diagonal components of the dielectric tensor. Moreover, the MO polar Kerr spectra of the samples were measured in an applied magnetic field of 1.5 T between 0.74 and 5.8 eV. The off-diagonal components of the dielectric tensor were then calculated by analyzing Kerr rotation, ellipticity, and the determined diagonal elements of the dielectric tensor. These functions yield information about the spin-dependent electronic structures of the LSMO thin films. We observed several MO-active transitions above 2 eV. These bands arise from the Mn-d͑t 2g ͒ to Mn-d͑e g ͒ in the majority-spin channel and the onset of O-2p to Mn-d͑e g ͒ and O-2p to Mn-d͑t 2g ͒ transitions in the minority-spin channel, in accord with the band-structure calculations. Most interestingly, their peak position and intensity are dependent on the film thickness, suggesting possible applications for tailoring MO responses in these PMA thin films.

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