Quenching of persistent photoconductivity and decrease of electron concentration by high electric fields in GaAs delta-doped by Sn on vicinal substrate structures

This paper reports the measurements of high electric field transport and the persistent photoconductivity in delta-doped by Sn on vicinal and singular substrate GaAs structures. Transport properties of the hot electron gas were measured in the temperature range 4.2 K < T < 300 K at high electric fields up to E = 10(4) V/cm in darkness and under illumination using a pulse technique. Dependence of the current density J(E) showed an anisotropy in [110] and [(1) over bar 10] directions in GaAs(delta-Sn) on vicinal substrate structures and histeresis in electric field at low temperatures. In GaAs(delta-Sn) on singular substrate structures the anisotropy of conductivity is small. The persistent photoconductivity was observed with well defined threshold T-c approximate to 240 K in GaAs(delta-Sn) on vicinal substrate structures. At T = 4.2 K by applying a high voltage the persistent photoconductivity may be quenched and the resistance of the sample increased by an order of magnitude. The high conductivity state arises again due to illumination of the sample or due to heating to temperatures above approximate to 240 K.