Article abstract
Nature Physics 3, 487 - 491 (2007)
Published online: 21 May 2007 | doi:10.1038/nphys622
Subject Categories: Materials physics | Condensed-matter physics
Order-by-disorder and spiral spin-liquid in frustrated diamond-lattice antiferromagnets
Doron Bergman1, Jason Alicea1, Emanuel Gull2, Simon Trebst3 & Leon Balents1
Abstract
Frustration refers to competition between different interactions that cannot be simultaneously satisfied—a familiar feature in many magnetic solids. Strong frustration leads to highly degenerate ground states and a large suppression of ordering by fluctuations. Key challenges in frustrated magnetism include the characterization of the fluctuating spin-liquid regime and determination of the mechanism of eventual order at lower temperature. Here, we study a model of a diamond-lattice antiferromagnet appropriate for numerous spinel materials. With sufficiently strong frustration, a massive ground-state degeneracy develops amongst spirals whose propagation wavevectors reside on a continuous two-dimensional 'spiral surface' in momentum space. We argue that an important ordering mechanism is entropic splitting of the degenerate ground states, an elusive phenomenon called 'order by disorder'. A broad spiral spin-liquid regime emerges at higher temperatures, where the underlying spiral surface can be directly revealed through spin correlations. We discuss the agreement between these predictions and the well-characterized spinel MnSc2S4.
- Department of Physics, University of California, Santa Barbara, California 93106-9530, USA
- Theoretische Physik, Eidgenössische Technische Hochschule Zürich, CH-8093 Zürich, Switzerland
- Microsoft Research, Station Q, University of California, Santa Barbara, California 93106, USA
Correspondence to: Doron Bergman1 e-mail: doronber@physics.ucsb.edu
MORE ARTICLES LIKE THIS
These links to content published by NPG are automatically generated.
NEWS AND VIEWS
Condensed-matter physics Magnetic frustration squeezed outNature News and Views (07 Nov 2002)
Quantum many-body physics 2D or not 2D?Nature Physics News and Views (01 Nov 2007)
See all 9 matches for News And ViewsRESEARCH
Pressure-induced crystallization of a spin liquidNature Letters to Editor (07 Nov 2002)
Emergent excitations in a geometrically frustrated magnetNature Letters to Editor (22 Aug 2002)
See all 35 matches for Research
