Electric field induced changes of the fundamental absorption and low‐temperature energy relaxation in n‐type GaSb

Abstract

The dependence of the absorption coefficient a on the photon energy is investigated for different degenerately doped samples of n-type GaSb in the region of the fundamental absorption. A comparison of the experimental data with the theory by Dyakonov e t al.shows satisfactory agreement for a > 500 crn-'. The application of pulsed electric fields a t a lattice temperature of 6 K gradually removes the Burstein-Moss shift.

Hot-electron energy relaxation in GaAs/GaAlAs two-dimensional structures: importance of two-phonon processes

“…Any uncertainty about the p value only alters the fitted D value as these two quantities enter the energy loss expression in the form D p 1/2 . It may be noted that Obiditsch and Kahlert [19] obtained a fair agreement between their calculations and ELR data in bulk n-GaSb using a value of D = 5.2 × 10 3 eV. Calculations of energy loss by Kubakaddi and Krishnamurthy [22] in bulk n-InSb agree with the experimental data for a D = 1.24 × 10 3 eV.…”

“…Ganguly and Ngai [21] have formulated an effective Hamiltonian for the interaction between electrons and two-phonons. Employing this formalism the energy loss rates are satisfactorily explained in InSb [22], GaAs [23] by Kubakaddi and co-workers and in GaSb [19] by Obditsch and Kahlert. Free carrier absorption in InSb [21] and mobility in Si [11] are also explained employing electron scattering by two-phonons.…”

“…By evaluating the ELRs for electron temperatures between 4.2 K and 18.0 K, they concluded that above 10 K the usual energy loss mechanisms involving single phonon interaction cannot describe the energy relaxation process and the data were highly suggestive of a two-phonon process involving 2TA phonons at the zone edge of the Brillouin zone. Obiditsch and Kahlert [19], from their studies of electric field-induced changes of the fundamental absorption in n-GaSb, have deduced ELRs as a function of electron temperature. A strong increase of transferred energy above 14 K is found.…”