Ordering of Dzyaloshinskii-Moriya vectors and unidirectional anisotropy in spin glasses

摘要

The mean-field theory of the Dzyaloshinskii-Moriya (DM) interaction in spin glasses is developed. Due to the fact that a microscopic DM vector is defined up to a sign there exist additional internal degrees of freedom caused by ordering of microscopic DM vectors below the freezing temperature. This is a reason for the appearance of the macroscopical unidirectional anisotropy. The value of the unidirectional anisotropy field is proportional to the value of the external cooling field a for weak H and runs to saturation at strong H.