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arXiv · 0808.2871

Torsional oscillator and synchrotron x-ray experiments on solid 4He in aerogel

N. Mulders·J. T. West·M. H. W. Chan·C. N. Kodituwakku·C. A. Burns·L. B. Lurio
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Abstract

X-ray diffraction experiments show that solid 4He grown in aerogel is highly polycrystalline, with a hcp crystal structure (as in bulk) and a crystallite size of approximately 100 nm. In contrast to the expectation that the highly disordered solid will have a large supersolid fraction, torsional oscillator measurements show a behavior that is strikingly similar to high purity crystals grown from the superfluid phase. The low temperature supersolid fraction is only ~3x10-4 and the onset temperature is ~ 100 mK.

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N. Mulders, J. T. West, M. H. W. Chan, C. N. Kodituwakku, C. A. Burns, L. B. Lurio. 2008-08-21. Torsional oscillator and synchrotron x-ray experiments on solid 4He in aerogel. https://doi.org/10.1103/physrevlett.101.165303

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