Quenching of photoconductivity by a strong electric field in tin delta-doped GaAs structures

The conductivity of GaAs structures delta-doped with tin on the vicinal and singular faces was investigated in strong electric fields up to E=10(4) V/cm and temperatures in the range 4.2 K <T<300 K. The measurements were performed in the dark and under illumination with visible light. Long-time photoconductivity of 2D electrons with threshold T-c approximate to 240 K was observed in samples which were delta-doped with tin on the vicinal face. A strong electric field not only quenches photoconductivity, but also increases the resistance of the structures at temperatures T<T-c by several orders of magnitude with respect to the dark resistance. (C) 1996 American Institute of Physics.