Abstract
The equilibrium superfluid phase of 3He impregnated into high-porosity (98%) silica aerogels appears to be a non-equal-spin-pairing state in zero field at all pressures, which is generally assumed to be the Balian-Werthamer (BW) phase modified by the depairing effects of the aerogel structure. The nuclear magnetic susceptibility played a key role in identifying the B-phase of pure 3He with the BW state. We report theoretical calculations of the nuclear magnetic susceptibility for the BW model of superfluid 3He in aerogel within the framework of the Fermi-liquid theory of superfluid 3He. Scattering of quasiparticles by the aerogel, in addition to Fermi-liquid exchange corrections, leads to substantial changes in the susceptibility of the BW phase. The increase in the magnetic susceptibility of 3He-aerogel compared to pure 3He-B is related to the polarizability of the gapless excitations and the impurity-induced local field. The limited data that is available is in rough agreement with theoretical predictions. Future measurements could prove important for a more definitive identification of the ordered phase, as well as for refining the theoretical model for the effects of disorder and scattering on the properties of superfluid 3He.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 115-142 |
| Number of pages | 28 |
| Journal | Journal of Low Temperature Physics |
| Volume | 125 |
| Issue number | 3-4 |
| DOIs | |
| State | Published - 2001 |
Funding
We thank Bill Halperin, Tom Haard, and Guillaume Gervais for enlightening discussions on the phase diagram and properties of superfluid 3He in aerogel. We thank Doug Osheroff for his comments on this manuscript and for providing us with a copy of the review in Ref. 10. This research was supported in part by the NSF through grant DMR-9972087.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- General Materials Science
- Condensed Matter Physics