Spin ice: magnetic excitations without monopole signatures using muon spin rotation.
نویسندگان
چکیده
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.
منابع مشابه
Low-temperature muon spin rotation studies of the monopole charges and currents in Y doped Ho2Ti2O7
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عنوان ژورنال:
- Physical review letters
دوره 107 20 شماره
صفحات -
تاریخ انتشار 2011