Raman spectroscopic determination of hole density in diluted magnetic semiconductor GaxMn1−xSb

Raman scattering determination of hole density has been reported in diluted magnetic semiconductor Ga_1-xMn_xSb prepared by Mn ions implantation, deposition, and post annealing. The Raman spectra measured from the implanted region of the sample show coupled plasmon LO-phonon mode (CPLOM), which is found to be superimposed with GaSb-like phonon modes in the spectra. The spectral lineshapes are modeled using a dielectric function where interband and intraband transitions of free holes are included. In addition to CPLOM, the individual contribution arises from GaSb-like phonon modes are taken into account in the model. The hole density as a function of laser probing position is determined from the best fit parameters and is found to be in reasonable agreement with the results obtained from the electrochemical capacitance-voltage technique. Furthermore, the dependence of optical mobility, depletion width, and peak frequency of CPLOM with hole density is determined.