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arXiv · 2102.11969

Experimental measurement of the isolated magnetic susceptibility

D. Billington·C. Paulsen·E. Lhotel·J. Cannon·E. Riordan·M. Salman·G. Klemencic·C. Cafolla-Ward·D. Prabhakaran·S. R. Giblin·S. T. Bramwell
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Abstract

The isolated susceptibility $\chi_{\rm I}$ may be defined as a (non-thermodynamic) average over the canonical ensemble, but while it has often been discussed in the literature, it has not been clearly measured. Here, we demonstrate an unambiguous measurement of $\chi_{\rm I}$ at avoided nuclear-electronic level crossings in a dilute spin ice system, containing well-separated holmium ions. We show that $\chi_{\rm I}$ quantifies the superposition of quasi-classical spin states at these points, and is a direct measure of state concurrence and populations.

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D. Billington, C. Paulsen, E. Lhotel, J. Cannon, E. Riordan, M. Salman, G. Klemencic, C. Cafolla-Ward, D. Prabhakaran, S. R. Giblin, S. T. Bramwell. 2021-02-23. Experimental measurement of the isolated magnetic susceptibility. https://doi.org/10.1103/physrevb.104.014418

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