Oblique spin-flip reflection of relativistic electrons from a potential barrier

The Dirac equation is used to describe oblique spin-conserving and spin-flip reflections of relativistic electrons from a one-dimensional potential barrier in a vacuum. When an electron hits the barrier from an oblique direction, its spin-up and spin-down states have different energies due to the spin-orbit interaction and the fact that the system has a structural inversion asymmetry. When the electron is reflected in an elastic spin-conserving process, incoming and outgoing angles are the same. If an elastic reflection is a spin-flip process, the outgoing angle is different from the incoming one. As a result, a beam of incoming spin-polarized electrons is split after the reflection into two beams. Angles and intensities of the reflected beams are calculated. Spin splitting of energies for relativistic electrons due to the spin-orbit interaction in an asymmetric quantum well is described.