Using the numerical solution to the time-dependent Dirac equation we show that the effect of relativity on the usual Larmor period for an electron in a magnetic field can be enhanced drastically if a suitably scaled and aligned static electric field is added to the interaction. This electric field does not change the electron's speed but leads to an elliptical spin precession due to relativity. This spin precession is accompanied by a position-dependent spin distribution.
Krekora, P; Su, Q; and Grobe, Rainer, "Electric-field-induced relativistic Larmor-frequency reduction" (2002). Faculty publications – Physics. Paper 29.