Dunsiger SR, Aczel AA, Arguello C, Dabkowska H, Dabkowski A, Du MH, Goko T, Javanparast B, Lin T, Ning FL, Noad HML, Singh DJ, Williams TJ, Uemura YJ, Gingras MJP, Luke GM. Spin ice: magnetic excitations without monopole signatures using muon spin rotation.
Phys Rev Lett 2011;
107:207207. [PMID:
22181768 DOI:
10.1103/physrevlett.107.207207]
[Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Indexed: 05/31/2023]
Abstract
Theory predicts the low temperature magnetic excitations in spin ices consist of deconfined magnetic charges, or monopoles. A recent transverse-field (TF) muon spin rotation (μSR) experiment [S. T. Bramwell et al., Nature (London) 461, 956 (2009)] reports results claiming to be consistent with the temperature and magnetic field dependence anticipated for monopole nucleation-the so-called second Wien effect. We demonstrate via a new series of μSR experiments in Dy(2)Ti(2)O(7) that such an effect is not observable in a TF μSR experiment. Rather, as found in many highly frustrated magnetic materials, we observe spin fluctuations which become temperature independent at low temperatures, behavior which dominates over any possible signature of thermally nucleated monopole excitations.
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