Low threshold and high Brillouin gain coefficients of piezoelectric semiconductor magneto-plasmas

Assuming that the origin of stimulated Brillouin scattering (SBS) lies in effective Brillouin susceptibility arising due to (i) current density dependent nonlinear induced polarization, and (ii) pump wave - acoustical phonon mode dependent electrostrictive polarization; expressions are obtained for the steady-state and transient Brillouin gain coefficients of weakly-piezoelectric semiconductors magneto-plasmas under different geometrical configurations of applied magnetic field. The threshold value of pump intensity and optimum value of pulse duration for the onset of transient SBS are estimated. For numerical calculations, n-InSb crystal at 77K temperature, acting as a Brillouin medium, is assumed to be irradiated by a pulsed CO2 laser. The influence of piezoelectric property of the Brillouin medium on threshold and Brillouin gain coefficients is analyzed. The dependence of Brillouin gain coefficients on doping concentration, applied magnetic field and its inclination, scattering angle and pump pulse duration are explored in detail with aim to determine suitable values of these controllable parameters to enhance Brillouin gain coefficients at lower pump powers, and to search the feasibility of Brillouin nonlinearities based efficient semiconductor optoelectronic devices.