相关论文: Broken Symmetry and Nonequilibrium Superfluid 3He
We report the discovery of the acoustic Faraday effect in superfluid 3He-B. The observation of this effect provides the first direct evidence for propagating transverse acoustic waves in liquid 3He, a mode first predicted by Landau in 1957.…
We discuss the relationship of collisionless sound propagation and attenuation to the order parameter collective modes of superfluid 3He-B. These modes, which reflect the symmetries of the normal state as well as the broken gauge and…
Due to its broken spin and orbit rotation symmetries, superfluid $^3$He plays a unique role for testing rotational quantum properties on a macroscopic scale. In this system the orbital momentum forms textures that provide an effective…
In superfluid 3He-B the off-resonant coupling of the J=2-, M=+/- 1 order parameter collective modes to transverse current excitations stabilizes propagating transverse waves with low damping for frequencies above that of the J=2- modes.…
We present results of transverse acoustics studies in superfluid ^{3}He-B at fields up to 0.11 T. Using acoustic cavity interferometry, we observe the Acoustic Faraday Effect for a transverse sound wave propagating along the magnetic field,…
It is established theoretically that an ordered state with continuous symmetry is inherently unstable to arbitrarily small amounts of disorder [1, 2]. This principle is of central importance in a wide variety of condensed systems including…
We have used the recently discovered acoustic Faraday effect in superfluid 3He to perform high resolution spectroscopy of an excited state of the superfluid condensate. With acoustic cavity interferometry we measure the rotation of the…
Liquid 3He at low temperatures is an ideal substance to study because of its natural purity. The superfluid state, which appears at temperatures below 3 mK, has many unusual and exciting properties. These have extensively been studied…
We present the first measurements of the attenuation of transverse sound in superfluid 3He-B. We use fixed path length interferometry combined with the magneto-acoustic Faraday effect to vary the effective path length by a factor of two,…
We have studied the acoustic Faraday effect in superfluid 3He up to significantly larger magnetic fields than in previous experiments achieving rotations of the polarization of transverse sound as large as 1710^{\circ}. We report nonlinear…
We have made simultaneous torsional oscillator and transverse NMR measurements (at 165 kHz) on 3He contained within aerogels with nominal densities of 1% and 2% of solid glass. The superfluid transition is seen simultaneously by both…
The role of 3He-3He collisions in our diffusion experiment is addressed and shown to not be relevant to the measurement of 3He diffusion against phonons in superfluid helium.
We present experimental, numerical and theoretical studies of a vortex front propagating into a region of vortex-free flow of rotating superfluid 3He-B. We show that the nature of the front changes from laminar through quasi-classical…
We show that a viscoelastic dispersion relation for shear waves in normal $^{3}$He at low temperatures follows directly from the Landau theory of normal Fermi liquids. This theoretical result is in accord with the experimental observations…
We have made precision measurements of the frequency of a collective mode of the superfluid 3He-B order parameter, the J=2- imaginary squashing mode. Measurements were performed at multiple pressures using interference of transverse sound…
Rapid new developments have occurred in superfluid hydrodynamics since the discovery of a host of unusual phenomena which arise from the diverse structure and dynamics of quantized vortices in 3He superfluids. These have been studied in…
Superfluid 3He is an unconventional neutral superfluid in a p-wave state with three different superfluid phases each identified by a unique set of characteristic broken symmetries and non- trivial topology. Despite natural immunity of 3He…
A normal-fluid component varying as T$^{2}$ is observed at very low temperatures in superfluid $^4$He and $^3$He-$^4$He mixture films adsorbed in alumina powder. The normal fluid appears to arise from thermally excited third sound that has…
The experimental investigation of superfluid turbulence in 3He-B is generally not possible with the techniques which have been developed for 4He-II. We describe a new method by which a transient burst of turbulent vortex expansion can be…
New techniques, both for generating and detecting turbulence in the helium superfluids 3He-B and 4He, have recently given insight in how turbulence is started, what the dissipation mechanisms are, and how turbulence decays when it appears…