Strong orientational effect of stretched aerogel on the 3He order parameter

Abstract

Deformation of aerogel strongly modifies the orientation of the order parameter of superfluid 3He confined in aerogel. We used a radial squeezing of aerogel to keep the orbital angular momentum of the 3He Cooper pairs in the plane perpendicular to the magnetic field. We did not find strong evidence for a "polar" phase, with a nodal line along the equator of the Fermi surface, predicted to occur at large radial squeezing. Instead we observed 3He-A with a clear experimental evidence of the destruction of the long-range order by random anisotropy -- the Larkin-Imry-Ma effect. In 3He-B we observed and identified new modes of NMR, which are impossible to obtain in bulk 3He-B. One of these modes is characterized by a repulsive interaction between magnons, which is suitable for the magnon Bose-Einstein condensation (BEC).

4 pages, 3 figures, revtex, submitted to PRL

References in corpus (4)

• On Larkin-Imry-Ma State of 3He-A in Aerogel
• Bose-Einstein condensation of magnons in superfluid 3He
• Magnon condensation into Q-ball in 3He-B
• Long-range correlated random field and random anisotropy O(N) models: A functional renormalization group study

Cited by in corpus (6)

• Bose-Einstein condensation of magnons in superfluid 3He
• Twenty years of magnon Bose condensation and spin current superfluidity in 3He-B
• Impurity Effects of Aerogel in Superfluid ${}^3$He
• Spin Vortex in Magnon BEC of Superfluid 3He-B
• Superfluid ${}^3$He in globally isotropic random media
• Superfluid Phase Stability of ${}^3$He in Axially Anisotropic Aerogel