Time parity violation in quantum and conventional magnets

Abstract

Time parity violation remains an exciting subject in Condensed Matter physics after recognition by Kramers, Wigner and Landau of its importance more than half a century ago. A huge amount of work has been done. Local probes like neutron scattering, EPR, NMR, μ-meson decay and lately X-ray scattering established, beyond any doubts, the existence of polarized spins in antiferromagnets and ferrites. Macroscopic experiments revealed new phenomena such as piezomagnetism and magnetoelectricity together with a wealth of nonlinear effects combining the magnetic and electric polarizations. Still there is a long way to go. In what follows I will enumerate some hot topics. First, two problems of the general interest in Condensed Matter Physics.

Key Words:

• magnets
• antiferromagnets
• magnetic symmetry