Raman spectra of In1-xGaxP under high pressure
The phonon modes in In1-xGaxP (InGaP) were investigated under high pressure by Raman scattering spectroscopy. In InGaP a pressure-induced structure was observed between LO and TO modes. The origin of this structure is discussed by means of dielectric analysis, pressure dependence and composition dependence. The authors conclude that a part of the high energy side of this additional structure is caused by a disorder-activated zone boundary optical phonon.