Memory effects in superfluid vortex dynamics

The dissipative dynamics of a vortex line in a superfluid is investigated within the frame of a non-Markovian quantal Brownian motion model. Our starting point is a recently proposed interaction Hamiltonian between the vortex and the superfluid quasiparticle excitations, whis is generalized to incor...

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Autores principales: Cataldo, H.M., Jezek, D.M.
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Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00222291_v136_n3-4_p217_Cataldo
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spelling todo:paper_00222291_v136_n3-4_p217_Cataldo2023-10-03T14:28:36Z Memory effects in superfluid vortex dynamics Cataldo, H.M. Jezek, D.M. 3He-4He mixtures Mutual friction Vortex dynamics Brownian movement Composition effects Elasticity Electron scattering Fermions Friction Hamiltonians Impurities Mathematical models Mixtures Thermal effects Vortex flow Elastic scattering Fermion impurities Friction coefficient Mutual friction Quantal Brownian motion model Rayfield-Reif formula Superfluid vortex dynamics Superfluid helium The dissipative dynamics of a vortex line in a superfluid is investigated within the frame of a non-Markovian quantal Brownian motion model. Our starting point is a recently proposed interaction Hamiltonian between the vortex and the superfluid quasiparticle excitations, whis is generalized to incorporate the effect of scattering from fermion inpurities (3He atoms). Thus, a non-Markovian equation of motion for the mean value of the vortex position operator is derived within a weak-coupling approximation. Such an eqaution is shown to yield, in the Markovian and elastic scattering limits, a 3He contribution to the longitudinal friction coefficient equivalent to that arising from the Rayfield-Reif formula. Simultaneous Markov and elastic scattering limits are found, however, to be incompatible, since an unexpected breakdown of the Markovian approximation is detected at low cyclotron frequencies. Then, a non-Markovian expression for the longitudinal friction coefficient is derived and computed as a function of temperature and 3He concentration. Such calculations show that cyclotron frequencies within the range 0.01-0.03 ps -1 yield a very good agreement to the longitudinal friction figures computed from te Iordanskii and Rayfield-Reif formulas for pure 4He, up to temperatures near 1 K. A similar performance is found for nonvanishing 3He concentrations, where the comparison is also shown to be very favourable with respect to the available experimental data. Memory effects are shown to be weak and increasing with temperature and concentration. © 2004 Springer Science+Business Media, Inc. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00222291_v136_n3-4_p217_Cataldo
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic 3He-4He mixtures
Mutual friction
Vortex dynamics
Brownian movement
Composition effects
Elasticity
Electron scattering
Fermions
Friction
Hamiltonians
Impurities
Mathematical models
Mixtures
Thermal effects
Vortex flow
Elastic scattering
Fermion impurities
Friction coefficient
Mutual friction
Quantal Brownian motion model
Rayfield-Reif formula
Superfluid vortex dynamics
Superfluid helium
spellingShingle 3He-4He mixtures
Mutual friction
Vortex dynamics
Brownian movement
Composition effects
Elasticity
Electron scattering
Fermions
Friction
Hamiltonians
Impurities
Mathematical models
Mixtures
Thermal effects
Vortex flow
Elastic scattering
Fermion impurities
Friction coefficient
Mutual friction
Quantal Brownian motion model
Rayfield-Reif formula
Superfluid vortex dynamics
Superfluid helium
Cataldo, H.M.
Jezek, D.M.
Memory effects in superfluid vortex dynamics
topic_facet 3He-4He mixtures
Mutual friction
Vortex dynamics
Brownian movement
Composition effects
Elasticity
Electron scattering
Fermions
Friction
Hamiltonians
Impurities
Mathematical models
Mixtures
Thermal effects
Vortex flow
Elastic scattering
Fermion impurities
Friction coefficient
Mutual friction
Quantal Brownian motion model
Rayfield-Reif formula
Superfluid vortex dynamics
Superfluid helium
description The dissipative dynamics of a vortex line in a superfluid is investigated within the frame of a non-Markovian quantal Brownian motion model. Our starting point is a recently proposed interaction Hamiltonian between the vortex and the superfluid quasiparticle excitations, whis is generalized to incorporate the effect of scattering from fermion inpurities (3He atoms). Thus, a non-Markovian equation of motion for the mean value of the vortex position operator is derived within a weak-coupling approximation. Such an eqaution is shown to yield, in the Markovian and elastic scattering limits, a 3He contribution to the longitudinal friction coefficient equivalent to that arising from the Rayfield-Reif formula. Simultaneous Markov and elastic scattering limits are found, however, to be incompatible, since an unexpected breakdown of the Markovian approximation is detected at low cyclotron frequencies. Then, a non-Markovian expression for the longitudinal friction coefficient is derived and computed as a function of temperature and 3He concentration. Such calculations show that cyclotron frequencies within the range 0.01-0.03 ps -1 yield a very good agreement to the longitudinal friction figures computed from te Iordanskii and Rayfield-Reif formulas for pure 4He, up to temperatures near 1 K. A similar performance is found for nonvanishing 3He concentrations, where the comparison is also shown to be very favourable with respect to the available experimental data. Memory effects are shown to be weak and increasing with temperature and concentration. © 2004 Springer Science+Business Media, Inc.
format JOUR
author Cataldo, H.M.
Jezek, D.M.
author_facet Cataldo, H.M.
Jezek, D.M.
author_sort Cataldo, H.M.
title Memory effects in superfluid vortex dynamics
title_short Memory effects in superfluid vortex dynamics
title_full Memory effects in superfluid vortex dynamics
title_fullStr Memory effects in superfluid vortex dynamics
title_full_unstemmed Memory effects in superfluid vortex dynamics
title_sort memory effects in superfluid vortex dynamics
url http://hdl.handle.net/20.500.12110/paper_00222291_v136_n3-4_p217_Cataldo
work_keys_str_mv AT cataldohm memoryeffectsinsuperfluidvortexdynamics
AT jezekdm memoryeffectsinsuperfluidvortexdynamics
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