Photon-induced intersubband scattering in a quantum ballistic channel
(QBC) is investigated. Our calculations show that light absorption in
a QBC with a non-uniform narrowed end can lead to a photovoltaic effec
t. Using a mode-matching technique the photocurrent is obtained. The e
valuated responsivity, detectivity and band width of the proposed phot
ovoltaic detector are conducive to practical application.