Field-tuned order-by-disorder in Ising frustrated magnets with antiferromagnetic interactions

P. C. GURUCIAGA; M. TARZIA; M. V. FERREYRA; L.F.CUGLIANDOLO; A. GRIGERA, S.; BORZI, R. A.

PHYSICAL REVIEW LETTERS

AMER PHYSICAL SOC

Lugar: New York; Año: 2016 vol. 117 p. 167203 - 167203

0031-9007

We demonstrate the appearance of thermal order-by-disorder (ObD) in Ising pyrochlores with staggered antiferromagnetic order frustrated by an applied magnetic field. We use a mean-field cluster variational method, alow-temperature expansion and Monte Carlo simulations to characterise the ObD transition. By direct evaluation of the density of states we quantitatively show how a symmetry-broken state is selected by thermal excitations. We discuss the relevance of our results to experiments in 2d and 3d samples, and evaluate how anomalous finite size effects could be exploited to detect this phenomenon experimentally in two-dimensional artificial systems, or in antiferromagnetic all-in?all-out pyrochlores like Nd2Hf2O7 or Nd2Zr2O7, for the first time.