Propagation of thermal excitations in a cluster of vortices in superfluid<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mrow /><mml:mn>3</mml:mn></mml:msup></mml:math>He-B

Hosio, J. J.; Eltsov, V. B.; Graaf, R. de; Krusius, M.; Mäkinen, J. T.; Schmoranzer, David

doi:10.1103/physrevb.84.224501

Cited by 18 publications

(32 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Superfluid turbulence experiments are currently performed in both 4 He 4-8 and in 3 He-B. [9][10][11][12][13][14] The methods used in these two liquids are different. In superfluid 3 He-B, at temperatures T T c , a powerful experimental technique, based on the Andreev scattering of thermal quasiparticle excitations, can be used to detect the vortex filaments; see for example the review article Ref.…”

Section: Introductionmentioning

confidence: 99%

Cross-sections of Andreev scattering by quantized vortex rings in3He-B

et al. 2012

View full text Add to dashboard Cite

We studied numerically the Andreev scattering cross-sections of three-dimensional isolated quantized vortex rings in superfluid 3 He-B at ultralow temperatures. We calculated the dependence of the cross-section on the ring's size and on the angle between the beam of incident thermal quasiparticle excitations and the direction of the ring's motion. We also introduced, and investigated numerically, the cross-section averaged over all possible orientations of the vortex ring; such a cross-section may be particularly relevant for the analysis of experimental data. We also analyzed the rôle of screening effects for Andreev reflection of quasiparticles by systems of vortex rings. Using the results obtained for isolated rings we found that the screening factor for a system of unlinked rings depends strongly on the average radius of the vortex ring, and that the screening effects increase with decreasing the rings' size.

show abstract

Section: Introductionmentioning

confidence: 99%

Cross-sections of Andreev scattering by quantized vortex rings in3He-B

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Temperature is measured using a quartz tuning fork thermometer [19] installed inside the sample tube approximately 20 mm above its lower end, which opens to the liquid 3 He volume with the sintered heat exchanger on the nuclear cooling stage. As the scattering of thermal quasiparticles from the sample walls is probably diffusive and there is a heat leak to the sample of the order of 12 pW [20], some temperature difference is expected along the cylinder from the NMR spectrometer to the thermometer fork. However, this possible temperature difference is small and does not affect the interpretation of results, as discussed below.…”

Section: Methodsmentioning

confidence: 99%

Relaxation of Bose-Einstein Condensates of Magnons in Magneto-Textural Traps in Superfluid 3He-B

et al. 2013

Self Cite

View full text Add to dashboard Cite

In superfluid3 He-B externally pumped quantized spin-wave excitations or magnons spontaneously form a Bose-Einstein condensate in a 3-dimensional trap created with the order-parameter texture and a shallow minimum in the polarizing field. The condensation is manifested by coherent precession of the magnetization with a common frequency in a large volume. The trap shape is controlled by the profile of the applied magnetic field and by the condensate itself via the spin-orbit interaction. The trapping potential can be experimentally determined with the spectroscopy of the magnon levels in the trap. We have measured the decay of the ground state condensates after switching off the pumping in the temperature range (0.14 ÷ 0.2)T c . Two contributions to the relaxation are identified: (1) spin diffusion with the diffusion coefficient proportional to the density of thermal quasiparticles and (2) the approximately temperature-independent radiation damping caused by the losses in the NMR pick-up circuit. The measured dependence of the relaxation on the shape of the trapping potential is in a good agreement with our calculations based on the magnetic field profile and the magnon-modified texture. Our values for the spin diffusion coefficient at low temperatures agree with the theoretical prediction and earlier measurements at temperatures above 0.5T c .

show abstract

“…The fork resonance width towards low temperatures is extrapolated using the weak-coupling-plus energy gap [31]. The heat leak into the sample cylinder was measured to be 12 pW in earlier experiments where the sample cylinder was separated from the sintered heat exchanger volume by a plate with a small orifice [32], using "black-body radiator" techniques [33]. …”

Section: Methodsmentioning

confidence: 99%

Microkelvin Thermometry with Bose–Einstein Condensates of Magnons and Applications to Studies of the AB Interface in Superfluid $$^3$$ 3 He

et al. 2014

Self Cite

View full text Add to dashboard Cite

Coherent precession of trapped Bose-Einstein condensates of magnons is a sensitive probe for magnetic relaxation processes in superfluid 3 He-B down to the lowest achievable temperatures. We use the dependence of the relaxation rate on the density of thermal quasiparticles to implement thermometry in 3 He-B at temperatures below 300 µK. Unlike popular vibrating wire or quartz tuning fork based thermometers, magnon condensates allow for contactless temperature measurement and make possible an independent in situ determination of the residual zero-temperature relaxation provided by the radiation damping. We use this magnon-condensate-based thermometry to study the thermal impedance of the interface between A and B phases of superfluid 3 He. The magnon condensate is also a sensitive probe of the orbital order-parameter texture. This has allowed us to observe for the first time the non-thermal signature of the annihilation of two AB interfaces.

show abstract

Propagation of thermal excitations in a cluster of vortices in superfluid3He-B

Cited by 18 publications

References 26 publications

Cross-sections of Andreev scattering by quantized vortex rings in3He-B

Cross-sections of Andreev scattering by quantized vortex rings in3He-B

Relaxation of Bose-Einstein Condensates of Magnons in Magneto-Textural Traps in Superfluid 3He-B

Microkelvin Thermometry with Bose–Einstein Condensates of Magnons and Applications to Studies of the AB Interface in Superfluid $$^3$$ 3 He

Contact Info

Product

Resources

About