E. Oh et al., OPTICAL-PROPERTIES OF MG-BASED II-VI TERNARIES AND QUATERNARIES - CD1-XMGXTE AND CD1-X-YMGXMNYTE, Physical review. B, Condensed matter, 48(20), 1993, pp. 15040-15046
We have investigated the photoluminescence, Raman, and infrared spectr
a of Cd-1-x,MgxTe and Cd1-x-yMgxMnyTe bulk crystals with the zinc-blen
de structure. From the band-gap (E(g)) photo- luminescence peak we ded
uce E(g)=1.595 + 1.607 + 1.592y eV at 10 K. The Raman spectra of the q
uaternary alloys exhibit a classic three-mode behavior with MgTe-like,
MnTe-like, and CdTe-like LO-TO pairs of zone-center optical phonons,
in decreasing order of frequency. Their composition dependence follows
the modified random-element isodisplacement model. For very small x a
nd/or y, the infrared absorption spectra recorded with a Fourier-trans
form spectrometer clearly reveal the local modes of Mn2+ and Mg2+. Mn2
+ exhibits one and Mg2+ three local modes corresponding to their isoto
pic abundances; the latter have frequencies proportional to 1/root M(M
g2+).