Growth and properties of Zn_{1–x –y}Bex Mny Se crystals

Abstract

Photoluminescence spectra, photoluminescence-excitation spectra, Raman and EPR studies were performed in bulk Zn 1-x-y Be x Mn y Se solid solutions grown by the high pressure Bridgman method in the range of composition 0 < x < 0.2, 0 < y < 0.2. For low Mn content photoluminescence spectra at low temperatures consist of exciton, "edge" and deep levels emission bands. The main yellow band (2.05 eV) is due to internal transition in Mn 2+. The exciton energy gap versus Mn content was determined for Zn 1-x-y Be x Mn y Se samples with Be content x = 0.05. EPR studies show that the g-factor is noticeably larger than the g free value indicating a large exchange interaction. The decreasing of g-factor with increasing Mn concentration in the investigated samples can be explained as due to increasing of spin ordering. Applying the DPPH as a standard, the concentration of unpaired spins per unit weight of the crystal was estimated. Measured at room temperature Raman spectra consist of ZnSe-like, MnSe-like and BeSe-like transverse (TO), longitudinal (LO), transverse (TA) and longitudinal (LA) phonon modes.

Optical and photothermal investigations of Zn1−x−yBexMnySe solid solutions

“…Zn 1− x − y Be x Mn y Se solid solution is very interesting material for its peculiar properties and potential application in construction of miniature magnetic field sensors, magnetic random access memory, spin‐transistors and applications of spin‐based electronics in quantum informatics. Up to date there is a number of papers concerning Zn 1− x Mn x Se but only a few papers have been published 1–4 dealing with preparation and properties of Zn 1− x − y Be x Mn y Se crystals and thin films. This work deals with photoacoustic and photoluminescence (PL) studies of bulk Zn 1− x − y Be x Mn y Se mixed crystals.…”

Photoacoustic method of determination of quantum efficiency of luminescence in Mn2+ ions in Zn1−x−yBexMnySe crystals

“…The novel and peculiar magnetic and optical properties of Mn containing II-VI solid solutions arise mainly from the properties of the electrical inactive Mn 2+ ion placed in the cation site [4]. Although Zn 1-x-y Be x Mn y Se mixed crystals are very promis− ing because of the possibility of the energy gap tuning by the change of Be concentration in the solution, the number of papers dealing with the growth and properties of Zn 1-x-y Be x Mn y Se solid solutions is very limited [5][6][7][8][9]. The method of determination of the quantum efficiency of the luminescence, presented in this paper, is based on the Ro− sencwaig and Gersho photoacoustic (PA) theory [10].…”