Rashba billiards
Absztrakt:
We study the energy levels of non-interacting electrons confined
to
move in two-dimensional billiard regions and having a spin-
dependent
dynamics due to a finite Rashba spin splitting. The free space
Green's
function for such Rashba billiards is constructed analytically
and used
to find the area and perimeter contributions to the density of
states,
as well as the corresponding smooth counting function. We show
that, in
contrast to systems with spin-rotational invariance, Rashba
billiards
always possess a negative energy spectrum. A semi-classical
analysis is
presented to interpret the singular behavior of the density of
states
at certain negative energies for circular Rashba billiards. Our
detailed analysis of the spin structure of circular Rashba
billiards
reveals a finite out-of-plane spin projection for electron
eigenstates.