Photoconductance measurement on TlInGaP grown by gas source MBE

TlInP, TIGaP and TlInGaP layers are grown by gas source MBE and the temperature-dependence of their band gap energy is characterized with the photoconductance measurement. This material system was recently proposed by us for 0.9 mu m to over 10 mu m optical devices as well as temperature-insensitive-wavelength laser diodes. Photoconductance measurements on TlInP and TlInGaP grown on InP substrates show that their band gap energies are narrower than that of InP and that the temperature variation of band gap energy is weaker than those of InP and InAs as expected. Furthermore, photoconductance measurements on TIGaP grown on GaAs substrates show the absorption in the 1.4 mu m wavelength region as well as the small temperature variation of absorption edge (band gap energy) as expected. (C) 1998 Elsevier Science B.V. All rights reserved.