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Theory for supersolid $^4$He

Xi Dai·Michael Ma·Fu-Chun Zhang
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Abstract

Although both vacancies and interstitial have relatively high activation energies in the normal solid, we propose that a lower energy bound state of a vacancy and an interstitial may facilitate vacancy condensation to give supersolidity in $^{4}$He . We use a phenomenological two-band boson lattice model to demonstrate this new mechanism and discuss the possible relevance to the recently observed superfluid-like, non-classical rotational inertial experiments of Kim and Chan in solid $^{4}$He. Some of our results may also be applicable to trapped bosons in optical lattices.

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Xi Dai, Michael Ma, Fu-Chun Zhang. 2005-01-17. Theory for supersolid $^4$He. https://doi.org/10.1103/physrevb.72.132504

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