Possible quantum liquid crystal phases of helium monolayers
Abstract
The second-layer phase diagrams of He and He adsorbed on graphite are investigated. Intrinsically rounded specific-heat anomalies are observed at 1.4 and 0.9 K, respectively, over extended density regions in between the liquid and incommensurate solid phases. They are identified to anomalies associated with the Kosterlitz-Thouless-Halperin-Nelson-Young type two-dimensional melting. The prospected low temperature phase (C2 phase) is a commensurate phase or a phase with quasi-bond-orientational order, both containing - defectons. In either case, this would be the first atomic realization of the , a new state of matter. From the large enhancement of the melting temperature over He, we propose to assign the observed anomaly of He-C2 phase at 1.4 K to the hypothetical supersolid or superhexatic transition.
Keywords
Cite
@article{arxiv.1406.4388,
title = {Possible quantum liquid crystal phases of helium monolayers},
author = {S. Nakamura and K. Matsui and T. Matsui and Hiroshi Fukuyama},
journal= {arXiv preprint arXiv:1406.4388},
year = {2016}
}
Comments
12 pages, 3 figures, 1 table