Photogalvanic current in electron gas over a liquid helium surface
M. V. Entin+, L. I. Magarill+*
+Rzhanov Institute of Semiconductor Physics SB of the RAS, 630090 Novosibirsk, Russia
*Novosibirsk State University, 630090 Novosibirsk, Russia
Abstract
We study the stationary surface photocurrent in 2D electron gas near the helium surface. Electron gas is assumed to be attracted to the helium surface due to the image attracting force and an external stationary electric field. The alternating electric field has both vertical and in-plane components. The photogalvanic effect originates from the periodic transitions of electrons between quantum subbands in
the vertical direction caused by a normal component of the
alternating electric field accompanied by synchronous in-plane
acceleration/deceleration due to the electric
field in-plane component. The effect needs vertical asymmetry of the system. The problem is considered
taking into account a friction caused by the electron-ripplon interaction. The photocurrent resonantly depends on the field frequency. The resonance occurs at field frequencies close to the distance between well subbands. The resonance is symmetric or antisymmetric depending on the kind (linear or circular) of polarization.