The effect of hydrostatic pressure on material parameters and electrical transport properties in bulk GaN

Experimental data for temperature dependence of electron transport properties in a bulk, low dislocation density, GaN sample at atmospheric pressure and 7.1 kbar have been presented. The data are representing a weak hydrostatic pressure dependence. Our quantitative analysis on its material parameters including: high and low dielectric constants (ε∞,εs)(ε∞,εs), longitudinal and transverse optical phonons (ωLO,ωTO)(ωLO,ωTO), and electronic effective mass (me∗) show a small fractional change of −0.12,−0.14,0.05,0.058−0.12,−0.14,0.05,0.058 and 0.089 (percent/kbar), respectively. These results are confirmed by the Hall-effect data analysis on the basis of charge neutrality condition and various scattering mechanisms.