NMR Frequency Shifts and Phase Identification in Superfluid $^3$He
Superconductivity
2018-11-14 v2
Abstract
The pressure dependence of the order parameter in superfluid He is amazingly simple. In the Ginzburg-Landau regime, i.e. close to , the square of the order parameter can be accurately measured by its proportionality to NMR frequency shifts and is strictly linear in pressure. This behavior is replicated for superfluid He imbibed in isotropic and anisotropic silica aerogels. The proportionality factor is constrained by the symmetry of the superfluid state and is an important signature of the corresponding superfluid phase. For the purpose of identifying various new superfluid states in the -wave manifold, the order parameter amplitude of He-A is a useful reference, and this simple pressure dependence greatly facilitates identification.
Cite
@article{arxiv.1808.07943,
title = {NMR Frequency Shifts and Phase Identification in Superfluid $^3$He},
author = {A. M. Zimmerman and M. D. Nguyen and W. P. Halperin},
journal= {arXiv preprint arXiv:1808.07943},
year = {2018}
}