Quantum spin systems such as magnetic insulators usually show magnetic order, but such classical states can give way to
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Anisotropic Melting of Frustrated Ising Antiferromagnets
Magnetic frustrations and dimensionality play an important role in determining the nature of the magnetic long-range order and how it melts at temperatures above the ordering transition TN. In this work, we use large-scale Monte Carlo simulations to study these phenomena in a class of frustrated Ising spin models in two spatial dimensions. We find that the melting of the magnetic long-range order into an isotropic gas-like paramagnet proceeds via an intermediate stage where the classical spins remain anisotropically correlated. This correlated paramagnet exists in a temperature range TN < T < T, whose width increases as magnetic frustrations grow. This intermediate phase is typically characterized by short-range correlations, however the two-dimensional nature of the
model allows for an additional exotic feature – formation of an incommensurate liquid-like phase with algebraically decaying spin correlations. The two-stage melting of magnetic order is generic and pertinent to many frustrated quasi-2D magnets with large (essentially classical) spins.
- Award ID(s):
- 1917511
- Publication Date:
- NSF-PAR ID:
- 10323675
- Journal Name:
- Physical review letters
- ISSN:
- 1092-0145
- Sponsoring Org:
- National Science Foundation
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