Photoresistive effect in δ-doped GaAs/metal tunnel junctions
Kotel'nikov I. N. , Shul'man A. Ya. , Varvanin N. A. , Ganichev S. D. , Mayerhofer B. , Prett W.
An increase of the resistance of a tunnel junction, formed by a two-dimensional electron gas of 5-doped GaAs and a metal film (gate) on a semiconductor surface, was observed under the action of pulsed sub-millimeter laser radiation. This response is opposite in sign to that expected from heating of two-dimensional electrons by radiation. It was found that the electrons in the <5-layer are heated and this heating is responsible for the positive photoconductivity due to the change in the resistance of the <S-layer itself. A comparison is made with the photoresistive effect in volume-doped tunnel junctions with a Schottky barrier and possible mechanisms of the formation of ponderomotive forces from the field of the electromagnetic wave which influence the tunneling resistance in the case of a two-dimensional electron gas are discussed. © 1995 American Institute of Physics.