Stark effect in the optical absorption in quantum wires

Abstract

We have calculated the effect of a transverse electric field on the ground and the first few excited states of the electrons confined in a quantum wire and used these results to examine the effect of the electric field on the intersubband optical absorption in such quantum wires. The electric field removes the degeneracies between several of the excited states in the wire, which leads to peaks in the intersubband optical absorption of the wire. The application of the electric field leads to a Stark shift of the electron energies, which is quadratic in the field at low fields but becomes almost linear in the field at high fields. The electric field shifts the peaks in a manner which depends upon the polarization of the optical field with respect to the applied electric field. We have also investigated the range of wire radii and electric fields at which the infinite well model is valid in a material where the height of the confining potential barrier is finite. We have found that for small wire radii and strong electric fields, the infinite well model breaks down.