Orbital mechanism of the circular photogalvanic effect in quantum wells
S. A. Tarasenko
A. F. Ioffe Physico-Technical Institute RAS, 194021 St. Petersburg, Russia
PACS: 73.50.Pz, 73.50.Bk, 78.67.De
Abstract
It is shown that the free-carrier (Drude) absorption of
circularly polarized radiation in quantum well structures leads to
an electric current flow. The photocurrent reverses its direction
upon switching the light helicity. A pure orbital mechanism of
such a circular photogalvanic effect is proposed that is based on
interference of different pathways contributing to the light
absorption. Calculation shows that the magnitude of the helicity
dependent photocurrent in n-doped quantum well structures
corresponds to recent experimental observations.