C. Monier et al., PHOTOCURRENT AND PHOTOLUMINESCENCE SPECTROSCOPY OF INASXP1-X INP STRAINED QUANTUM-WELLS GROWN BY CHEMICAL BEAM EPITAXY/, Journal of crystal growth, 188(1-4), 1998, pp. 332-337
We report on optical investigations carried out on InAsxP1-x/InP singl
e and multi-quantum well structures with arsenic compositions of 0.35
< x < 0.54 and various well widths grown by chemical beam epitaxy. Sha
rp well-defined satellite peaks observed on X-ray diffraction patterns
suggest good interface quality achieved by improving growth interrupt
ion sequences. In addition, the strained quantum wells exhibit intense
and narrow luminescence peaks at low temperature. Doublet and multipl
et luminescence lines are assigned to emission from well thicknesses f
luctuating by one monolayer. The experimental well-resolved absorption
peaks observed from photocurrent spectra are attributed to electron-h
eavy-hole and electron-light-hole fundamental excitonic transitions. E
nergies deduced from measurements are compared with calculations withi
n the framework of the envelope-function formalism. The strain-induced
coupling between the light hole and spin-orbit valence bands and the
electron-effective mass modification along the quantification axis of
the quantum well (QW) are considered. The strained band-offset ratio Q
(C) is chosen as one adjustable parameter. An excellent agreement betw
een measured and calculated light and heavy exciton splitting energy i
s achieved with a Q(C) value of 0.70 +/- 0.02 and using structural par
ameters determined from X-ray diffraction analysis. In addition, Q(C)
appears to be independent of the arsenic composition in the present ra
nge. (C) 1998 Elsevier Science B.V. All rights reserved.