Regensburg 2000 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

AM: Magnetismus

AM 22: Spektroskopie II

AM 22.2: Talk

Thursday, March 30, 2000, 14:45–15:00, H22

A Generalized Ginzburg-Landau Approach to Second Harmonic Generation — •Debanand Sa, Roser Valenti, and Claudius Gros — Fachbereich Physik, Universität des Saarlandes, 66041 Saarbrück en

We develop a generalized Ginzburg-Landau theory for second harmonic generation (SHG) in magnets by expanding the free energy in terms of the order parameter in the magnetic phase and the susceptibility tensor in the corresponding high-temperature phase. The non-zero components of the SHG susceptibility in the ordered phase are derived from the symmetries of the susceptibility tensor in the high-temperature phase and the symmetry of the order parameter. In this derivation, the dependence of the SHG susceptibility on the order parameter follows naturally, and therefore its nonreciprocal optical properties. We examine this phenomenology for the magnetoelectric compound Cr₂O₃.