Raman spectroscopic determination of hole density in diluted magnetic semiconductor Ga<inf>x</inf>Mn<inf>1&#x2212;x</inf>Sb

Abstract

Raman scattering determination of hole density has been reported in diluted magnetic semiconductor Ga 1-x Mn x Sb prepared by Mn ions implantation, deposition, and post annealing. The Raman spectra measured from the implanted region of the sample show coupled plasmon LOphonon 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.