Raman, Photoluminescence and Photoacoustic Investigations of Zn1-x-yBexMnySe Mixed Crystals

Abstract

Quaternary diluted magnetic semiconductor Zn 1--x--y Be x Mn y Se (0 < x < 0.25, 0 < y < 0.50) were grown by the Bridgman method. Raman scattering, photoluminescence and photoacoustic spectra were measured. The energy gap and thermal diffusivity values at room temperature were estimated from these measurements.

Vibrational spectroscopy of compound semiconductor nanocrystals

“…The optical properties of quaternary II-VI semiconductor solid solutions are closely related to the lattice dynamics, which can be more complicated than in ternary systems. To our knowledge, only a quite limited number of theoretical and experimental studies devoted to the lattice dynamics of quaternary II-VI bulk single crystals or epitaxial layers have been reported so far [21,323,[362][363][364][365][366][367][368]. Depending on the type of compositional transformation of the phonon spectra (one-mode or two-mode) for the corre sponding ternary systems, a quaternary system can typically exhibit a two-mode or three-mode (multimode) behaviour.…”

“…Depending on the type of compositional transformation of the phonon spectra (one-mode or two-mode) for the corre sponding ternary systems, a quaternary system can typically exhibit a two-mode or three-mode (multimode) behaviour. For example, two-mode behaviour was observed for Zn 1−x Cd x Se 1−y Te y [362], while a three-mode type of the phonon spectrum behaviour was reported for CdS 1−x−y Se x Te y [363,364], ZnS 1−x−y Se x Te y [363], Cd 1−x−y Zn x Mn y Te [365], Cd 1−x−y Zn x Mg y Te [21], Zn 1−x−y Cd x Hg y Te [366], and Zn 1−x−y Be x Mn y Se [368]. Note that in most cases, the experimental data were obtained for quite a limited set of compositions.…”

“…Note that in most cases, the experimental data were obtained for quite a limited set of compositions. Moreover, the observed Raman spectra can be encumbered by frequency overlap of Raman bands corresponding to different sublattices (due to the small difference of the corresponding atomic masses) [368] or anharmonic resonance between one-phonon and twophonon bands [362].…”