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arXiv · 2302.01258

Magnetic Susceptibility of Andreev Bound States in Superfluid $^3$He-B

J. W. Scott·M. D. Nguyen·D. Park·W. P. Halperin
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Abstract

Nuclear magnetic resonance measurements of the magnetic susceptibility of superfluid $^3$He imbibed in anisotropic aerogel reveal anomalous behavior at low temperatures. Although the frequency shift clearly identifies a low-temperature phase as the $B$ phase, the magnetic susceptibility does not display the expected decrease associated with the formation of the opposite-spin Cooper pairs. This susceptibility anomaly appears to be the predicted high-field behavior corresponding to the Ising-like magnetic character of surface Andreev bound states within the planar aerogel structures.

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J. W. Scott, M. D. Nguyen, D. Park, W. P. Halperin. 2023-02-02. Magnetic Susceptibility of Andreev Bound States in Superfluid $^3$He-B. https://doi.org/10.1103/physrevlett.131.046001

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