1204.2168 (D. D. Khalyavin et al.)

A possible chiral spin-liquid phase in non-centrosymmetric
$R$BaCo$_4$O$_7$    [PDF]

D. D. Khalyavin, P. Manuel, L. C. Chapon

Based on a symmetry approach, we propose a possible explanation of the weak ferromagnetic component recently observed in YBaCo$_3$FeO$_7$ (Valldor et al. Phys Rev B, $\bf {84}$ 224426 (2011)) and other isostructural compounds in the high-temperature spin-liquid phase. Due to the polar nature of their crystal structure, a coupling between time-odd scalar spin chirality which we suggest as the primary order parameter and macroscopic magnetization is possible as follows from the general form of the appropriate free-energy invariant. The deduced pseudoproper coupling between both physical quantities provides a unique possibility to study the critical behaviour of the chiral order parameter.

View original: http://arxiv.org/abs/1204.2168