Transient Thermoelectric Effects in GaAs Crystals

Publisher Website
Google Scholar
Abstract
Dynamic measurements of thermal diffusion processes of conduction carriers and phonons in GaAs crystals have been made in the temperature range 80–300 K using a pulsed laser-induced “transient thermoelectric (TTE)” effect. The initial stage of the decay curves of TTE voltages gives the carrier recombination times τr, from which capture cross sections for electrons and holes are evaluated. During the second stage, three relaxation processes with relaxation times τf, τm, and τs were observed in both n- and p-GaAs; the fast, intermediate, and slow components are associated with electrons at the Γ, X, and L point conduction bands for n-GaAs, and the light, split-off band, and heavy holes for p-GaAs, respectively. The final stage yields the thermal diffusion coefficient D T and the thermal conductivity κ for phonons in these crystals.