Wave packet dynamics in a two-dimensional electron gas with spin orbit coupling:: Splitting and zitterbewegung

We study the effect of splitting and Zitterbewegung of one- and two-dimensional electron wave packets in the semiconductor quantum well under the influence of the Rashba spin orbit coupling. Results of our investigations show that the spin orbit interaction induces dramatic qualitative changes in the evolution of spin-polarized wave packet. The initial wave packet with spin polarization splits into two parts, which propagate with unequal group velocity. This splitting appears due to the presence of two branches of electron spectrum corresponding to the stationary states with different chirality. It is also demonstrated that in the presence of external magnetic field B perpendicular to the electron-gas plane the wave packet splits into two parts, which rotate with different cyclotron frequencies. It was shown that after some periods, the electron density distributes around cyclotron orbit and the motion acquires an irregular character. Our calculations were made for both cases of weak and strong spin orbit couplings.