Spin-polarized beam splitter for ballistic electrons

It is shown that in ballistic quasi two-dimensional electron systems momentum jumps of spin-polarized electrons appear whenever an increasing in-plane magnetic field depopulates magnetoelectric sub-bands at low temperatures. The system acts as a polarized beam splitter, the filtered spin-polarized electrons being spatially separated from the mainstream electron current. The momentum jumps can be also used to implement quantum logic states or electron switches.