Kerr magneto-optic effect in ferromagnetic CrBr3

摘要

In ferromagnetic CrBr3 the Kerr rotation is a significant effect which is not fully understood. Early investigations suggested that t1u(π)->t*2g and t2u(π)->t*2g and t1u(σ)->e*g and/or t*2g->t*1u were the contributing transitions. Recent investigations have overturned those assignments. Instead, a pair of transitions, t1u(π)->e*g and t2u(π)->e*g, with negative and positive spin-orbit coupling coefficients respectively, were shown to explain the Kerr rotation. A simplistic LCAO calculation on a small cluster, combined with Gaussian fits to data, supports those reassignments. We present results of a similar LCAO calculation and Gaussian fit for CrCl3.