Soft modes in the easy plane pyrochlore antiferromagnet

Abstract

Thermal fluctuations lift the high ground state degeneracy of the classical nearest neighbour pyrochlore antiferromagnet, with easy plane anisotropy, giving a first order phase transition to a long range ordered state. We show, from spin wave analysis and numerical simulation, that even below this transition a continuous manifold of states, of dimension N^{2/3} exist (N is the number of degrees of freedom). As the temperature goes to zero a further `order by disorder' selection is made from this manifold. The pyrochlore antiferromagnet Er_2Ti_2O_7, is believed to have an easy plane anisotropy and is reported to have the same magnetic structure. The latter is perhaps surprising, given that the dipole interaction lifts the degeneracy of the classical model in favour of a different structure. We interpret our results in the light of these facts.

arXiv comment7 pages, 9 figures, to appear in JPCM - HFM2003 conference proceeding

References in corpus (6)

• Spin Ice State in Frustrated Magnetic Pyrochlore Materials
• Properties of a classical spin liquid: the Heisenberg pyrochlore antiferromagnet
• Ising pyrochlore magnets: Low temperature properties, ice rules and beyond
• Er2Ti2O7: Evidence of Order by Disorder in a Frustrated Antiferromagnet
• Order induced by dipolar interactions in a geometrically frustrated antiferromagnet
• Field induced transitions in a kagome antiferromagnet

Cited by in corpus (40)

• Magnetic Pyrochlore Oxides
• Dipolar spin correlations in classical pyrochlore magnets
• Frustrated quantum rare-earth pyrochlores
• Definitive Evidence for Order-by-Quantum-Disorder in Er2Ti2O7
• Quantum order by disorder and accidental soft mode Er2Ti2O7
• Theory of multiple--phase competition in pyrochlore magnets with anisotropic exchange, with application to Yb2Ti2O7, Er2Ti2O7 and Er2Sn2O7
• Living on the edge : ground-state selection in quantum spin-ice pyrochlores
• Quantum and Classical Phases of the Pyrochlore Heisenberg Model with Competing Interactions
• Are multiphase competition & order-by-disorder the keys to understanding Yb2Ti2O7?
• Magnetic state of pyrochlore Cd2Os2O7 emerging from strong competition of ligand distortions and longer-range crystalline anisotropy
• Order by Disorder Spin Wave Gap in the XY Pyrochlore Magnet Er2Ti2O7
• Ground State Phase Diagram of Generic XY Pyrochlore Magnets with Quantum Fluctuations
• Magnetic order, magnetic correlations and spin dynamics in the pyrochlore antiferromagnet Er2Ti2O7
• Energetic selection of ordered states in a model of the Er2Ti2O7 frustrated pyrochlore XY antiferromagnet
• Phase Transition and Thermal Order-by-Disorder in the Pyrochlore Quantum Antiferromagnet Er2Ti2O7: a High-Temperature Series Expansion Study
• Order-by-Disorder in the XY Pyrochlore Antiferromagnet Revisited
• Single-ion properties of the $S_{eff}$ = 1/2 XY antiferromagnetic pyrochlores, Na$A^{\prime }$Co${}_2$F${}_7$ ($A^{\prime }=$ Ca${}^{2+}$, Sr${}^{2+}$)
• Ground state selection in XY pyrochlore antiferromagnets R${}_2$Ge${}_2$O${}_7$ (R = Er, Yb)
• Order by Disorder and Energetic Selection of the Ground State in the XY Pyrochlore Antiferromagnet Er2Ti2O7. An Inelastic Neutron Scattering Study
• Single-ion anisotropy in the gadolinium pyrochlores studied by an electron paramagnetic resonance
• Static and dynamic XY-like short-range order in a frustrated magnet with exchange disorder
• Nature of finite-temperature transition in anisotropic pyrochlore Er2Ti2O7
• Order from structural disorder in $XY$ pyrochlore antiferromagnet $\mathrm{E}{\mathrm{r}}_2\mathrm{T}{\mathrm{i}}_2{\mathrm{O}}_7$
• Order-by-disorder near criticality in $XY$ pyrochlore magnets
• XY Antiferromagnetic Ground State in the Effective S=1/2 Pyrochlore Yb2Ge2O7
• Magnetic excitations in the XY-pyrochlore antiferromagnet Er${}_2$Ti${}_2$O${}_7$
• Generic nearest-neighbour kagome model: XYZ & Dzyaloshinskii-Moriya, and comparison to pyrochlore
• Palmer-Chalker correlations in the XY pyrochlore antiferromagnet Er2Sn2O7
• Magnetization Process of the Classical Heisenberg Model on the Shastry-Sutherland Lattice
• Magnetic excitations in dipolar pyrochlore antiferromagnet Gd${}_2$Sn${}_2$O${}_7$
• Order Induced by Dilution in Pyrochlore XY Antiferromagnets
• Field induced multiple order-by-disorder state selection in antiferromagnetic honeycomb bilayer lattice
• Spin freezing in the disordered pyrochlore magnet NaCaCo${}_2$F${}_7$: NMR studies and Monte-Carlo simulations
• Low-field behavior of an XY pyrochlore antiferromagnet: emergent clock anisotropies
• Control of effective free energy landscape in a frustrated magnet by a field pulse
• The magnetic structure of Gd_2Ti_2O_7
• Low-temperature magnetisation process in the cubic pyrochlore quantum antiferromagnet, Er2Ti2O7
• The Magnetic Structure of $E{r}_{2}T{i}_2{O}_7$
• Traversing the pyrochlore stability diagram; microwave-assisted synthesis and discovery of mixed B-site Ln${}_2$InSbO${}_7$ family
• Constructing Emergent U(1) Symmetries in the Gamma-prime $\left({\mathbf{\Gamma }}^{\prime }\right)$ model