Quenched chirality in RbNiCl$_3$

Details Quenched chirality in RbNiCl$_3$ Quenched chirality in RbNiCl$_3$

2004-06-06

arxiv.org/abs/cond-mat/0406144v3

Phys. Rev. B 70, 224420 (2004)

Physics

Condensed Matter

Other Condensed Matter

Scientific paper

10.1103/PhysRevB.70.224420

The critical behaviour of stacked-triangular antiferromagnets has been intensely studied since Kawamura predicted new universality classes for triangular and helical antiferromagnets. The new universality classes are linked to an additional discrete degree of freedom, chirality, which is not present on rectangular lattices, nor in ferromagnets. However, the theoretical as well as experimental situation is discussed controversially, and generic scaling without universality has been proposed as an alternative scenario. Here we present a careful investigation of the zero-field critical behaviour of RbNiCl$_3$, a stacked-triangular Heisenberg antiferromagnet with very small Ising anisotropy. From linear birefringence experiments we determine the specific heat exponent $\alpha$ as well as the critical amplitude ratio $A^+/A^-$. Our high-resolution measurements point to a single second order phase transition with standard Heisenberg critical behaviour, contrary to all theoretical predictions. From a supplementary neutron diffraction study we can exclude a structural phase transition at T$_N$. We discuss our results in the context of other available experimental results on RbNiCl$_3$ and related compounds. We arrive at a simple intuitive explanation which may be relevant for other discrepancies observed in the critical behaviour of stacked-triangular antiferromagnets. In RbNiCl$_3$ the ordering of the chirality is suppressed by strong spin fluctuations, yielding to a different phase diagram, as compared to e.g.\@ CsNiCl$_3$, where the Ising anisotropy prevents these fluctuations.

Affiliated with

Also associated with

No associations

Rating

Quenched chirality in RbNiCl$_3$ does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Quenched chirality in RbNiCl$_3$, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quenched chirality in RbNiCl$_3$ will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-382199