Investigation on p-In0.51Ga0.49As LOPC Mode by Raman Spectra

Heavily P type In0.51Ga0.49As was grown with hole concentration from 3.3E19cm-3 to 4.6E19cm-3. Standard (001) surface Raman backscattering geometry was used to measure samples. Two mode behavior and LO phonon-plasmon-coupled mode (LOPC) were observed obviously. Raman peak of LOPC mode is insensitive to hole concentration. The full width at half maximum (FWHM) of LOPC and the intensity ratio of GaAs-like LO mode and LOPC mode depend on hole concentration. The coupling strength of GaAs-like LO mode and plasmons is weak when hole concentration is very high and Raman peak of LOPC mode is independence with increasing hole concentration.