CdS/CdSe intrinsic Stark superlattices
作者:
M. P. Halsall,
J. E. Nicholls,
J. J. Davies,
B. Cockayne,
P. J. Wright,
期刊:
Journal of Applied Physics
(AIP Available online 1992)
卷期:
Volume 71,
issue 2
页码: 907-915
ISSN:0021-8979
年代: 1992
DOI:10.1063/1.351312
出版商: AIP
数据来源: AIP
摘要:
Strained layer superlattices of wurtzite CdS/CdSe have been grown on (111)A GaAs substrates by metalorganic chemical vapor deposition and their optical properties studied by photoluminescence spectroscopy. It is shown that the superlattice layers contain giant strain‐induced piezoelectric fields exceeding 2×108V m−1. These fields are similar to those reported for (111) orientated III–V superlattices, but an order of magnitude greater. The recombination energies from a series of samples provide evidence for a type II conduction band offset of 0.23±0.10 eV (the electron wells being in the CdS), with the band structure heavily modified by the internal electric fields. In addition, the photoluminescence peak emission energy shows a strong dependence on the excitation power. This is interpreted as further evidence for the effect of internal fields. We conclude that this system shows new effects not previously observed in II–VI compound superlattices. The large band‐gap tunability and the space‐charge effects offer possibilities for all‐optical switching devices in the 700–1300‐nm region of the spectrum.
点击下载:
PDF
(1115KB)
返 回