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Anomalous low temperature specific heat of He-3 inside nanotube bundles

S. M. Gatica·F. Ancilotto·M. W. Cole
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Abstract

Helium atoms and hydrogen molecules can be strongly bound inside interstitial channels within bundles of carbon nanotubes. An exploration of the low energy and low temperature properties of He-3 atoms is presented here. Recent study of the analogous He-4 system has shown that the effect of heterogeneity is to yield a density of states N(E) that is qualitatively different from the one-dimensional (1D) form of N(E) that would occur for an ideal set of identical channels. In particular, the functional form of N(E) is that of a 4D gas near the very lowest energies and a 2D gas at somewhat higher energies. Similar behavior is found here for He-3. The resulting thermodynamic behavior of this fermi system is computed, yielding an anomalous form of the heat capacity and its dependence on coverage.

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S. M. Gatica, F. Ancilotto, M. W. Cole. 2004-04-14. Anomalous low temperature specific heat of He-3 inside nanotube bundles. https://doi.org/10.1023/b%3Ajolt.0000038521.03196.f3

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