Onsager-Kraichnan Condensation in Decaying Two-Dimensional Quantum Turbulence

Billam, Thomas P.; Reeves, Matthew T.; Anderson, Brian P.; Bradley, Ashton S.

doi:10.1103/physrevlett.112.145301

Cited by 107 publications

(138 citation statements)

References 63 publications

Supporting

Mentioning

134

Contrasting

Order By: Relevance

“…While intended as a model of twodimensional fluids in general, Onsager noted that the model was potentially particularly relevant for two-dimensional superfluids, whose vortices have quantized circulation and uniform size. Simulations of the two-dimensional GPE have shown how it is possible to dynamically evolve to the negative temperature Onsager vortex state [303,304]. Starting with a random configuration of vortices and antivortices one might expect the vortices and antivortices to evaporate from the BEC via pairwise annihilation and re-thermalization of the emitted sound, simply resulting in a BEC with an increased temperature.…”

Section: Vortex Lattices In the Supersolid Phasementioning

confidence: 99%

Vortices and vortex lattices in quantum ferrofluids

Martin

Marchant

O’Dell

et al. 2017

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The experimental realization of quantum-degenerate Bose gases made of atoms with sizeable magnetic dipole moments has created a new type of fluid, known as a quantum ferrofluid, which combines the extraordinary properties of superfluidity and ferrofluidity. A hallmark of superfluids is that they are constrained to rotate through vortices with quantized circulation. In quantum ferrofluids the long-range dipolar interactions add new ingredients by inducing magnetostriction and instabilities, and also affect the structural properties of vortices and vortex lattices. Here we give a review of the theory of vortices in dipolar Bose-Einstein condensates, exploring the interplay of magnetism with vorticity and contrasting this with the established behaviour in non-dipolar condensates. We cover single vortex solutions, including structure, energy and stability, vortex pairs, including interactions and dynamics, and also vortex lattices. Our discussion is founded on the mean-field theory provided by the dipolar Gross-Pitaevskii equation, ranging from analytic treatments based on the Thomas-Fermi (hydrodynamic) and variational approaches to full numerical simulations. Routes for generating vortices in dipolar condensates are discussed, with particular attention paid to rotating condensates, where surface instabilities drive the nucleation of vortices, and lead to the emergence of rich and varied vortex lattice structures. We also present an outlook, including potential extensions to degenerate Fermi gases, quantum Hall physics, toroidal systems and the Berezinskii-Kosterlitz-Thouless transition.

show abstract

Section: Vortex Lattices In the Supersolid Phasementioning

confidence: 99%

Vortices and vortex lattices in quantum ferrofluids

Martin

Marchant

O’Dell

et al. 2017

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…This kind of vortex clustering is theoretically investigated by the GP equation and Monte Carlo calculation [145,146,148,149]. Recently, Simula et al found that such a negative temperature state is dynamically formed through the evaporative heating of vortex when the disk-shaped flat potential is used [146] 1 .…”

Section: Formation Of the Onsager Vortex Of 2d Qtmentioning

confidence: 99%

“…There are many studies for 2D QT [129,130,138,139,140,141,142,143,144,145,146,147,148,149], some of which discuss the possibility of the inverse cascade in QT. To our understanding, the existence of the inverse cascade in QT is controversial.…”

Section: Inverse Cascade Of 2d Qtmentioning

confidence: 99%

Numerical Studies of Quantum Turbulence

2017

View full text Add to dashboard Cite

We review numerical studies of quantum turbulence. Quantum turbulence is currently one of the most important problems in low temperature physics and is actively studied for superfluid helium and atomic Bose-Einstein condensates. A key aspect of quantum turbulence is the dynamics of condensates and quantized vortices. The dynamics of quantized vortices in superfluid helium are described by the vortex filament model, while the dynamics of condensates are described by the Gross-Pitaevskii model. Both of these models are nonlinear, and the quantum turbulent states of interest are far from equilibrium. Hence, numerical studies have been indispensable for studying quantum turbulence. In fact, numerical studies have contributed in revealing the various problems of quantum turbulence. This article reviews the recent developments in numerical studies of quantum turbulence. We start with the motivation and the basics of quantum turbulence and invite readers to the frontier of this research. Though there are many important topics in the quantum turbulence of superfluid helium, this article focuses on inhomogeneous quantum turbulence in a channel, which has been motivated by recent visualization experiments. Atomic Bose-Einstein condensates are a modern issue in quantum turbulence, and this article reviews a variety of topics in the quantum turbulence of condensates e.g. two-dimensional quantum turbulence, weak wave turbulence, turbulence in a spinor condensate, etc., some of which has not been addressed in superfluid helium and paves the novel way for quantum turbulence researches. Finally we discuss open problems.

show abstract

“…While the BEC itself is three-dimensional, the dynamics of the vortices are essentially two-dimensional [31,33]. In contrast to previous theoretical studies of quasi-two dimensional quantum turbulent systems in harmonic traps [34,35] or in uniform doubly-periodic domains [16,[36][37][38], we consider a BEC confined in a disc trap. Details of these simulations are provided in the Supplemental Material [39].…”

mentioning

confidence: 99%

Emergence of Order from Turbulence in an Isolated Planar Superfluid

2014

View full text Add to dashboard Cite

We study the relaxation dynamics of an isolated zero temperature quasi-two-dimensional superfluid Bose-Einstein condensate (BEC) that is imprinted with a spatially random distribution of quantum vortices. Following a period of vortex annihilation, we find that the remaining vortices self-organise into two macroscopic coherent 'Onsager vortex' clusters that are stable indefinitely. We demonstrate that this occurs due to a novel physical mechanism -the evaporative heating of the vortices -that results in a negative temperature phase transition in the vortex degrees of freedom. At the end of our simulations the system is trapped in a non-thermal state. Our computational results provide a pathway to observing Onsager vortex states in a superfluid Bose gas.The question of how thermodynamics arises from unitary quantum evolution [1] has been debated since the early days of quantum mechanics. The closest laboratory realisation of an isolated quantum system of many particles is perhaps the ultracold quantum gas, and recent progress in the control and manipulation of these systems mean that the question is no longer simply an academic one [2]. A particular focus has been one-dimensional Bose gases as described by the Lieb-Liniger model [3], as the integrability of the model suggests that it may be prevented from attaining thermal equilibrium following a quench [4]. Indeed, two groundbreaking experiments on the dynamics of one-dimensional Bose gases [5,6] sparked a rush of further activity due to their seemingly contradictory results on whether the experiments returned to standard thermal equilibrium. These experiments have generated significant recent theoretical interest in the nonequilibrium dynamics and relaxation of idealised isolated quantum systems following a disturbance [2,[7][8][9].The quantum relaxation of higher dimensional isolated quantum systems is difficult to address computationally due to their exponential complexity. Recent experiments have quenched the interatomic interaction strength of 3D BECs in oblate and spherical harmonic traps and followed the subsequent dynamics [10,11], including apparent saturation of the momentum distribution [10]. However the relevance of quantum dynamics in their relaxation is not clear. In some situations the classical field approximation [12,13] can provide insight to quench dynamics. Indeed, recent theoretical work has considered the classical equilibration dynamics of 2D superfluids following a quench from the perspectives of turbulence and non-thermal fixed points [14][15][16][17][18][19].The thermalisation of isolated classical systems is generally understood in terms of ergodicity and chaotic dynamics [20]. Even though the equations of motion of a physical system are entirely reversible, if a system with a sufficiently large number of degrees of freedom begins in an 'atypical' state -such as a gas with all particles in one half of the container -it will quickly relax to a more 'typical' state consistent with thermal equilibrium as predicted by statistical mechanics...

show abstract

Onsager-Kraichnan Condensation in Decaying Two-Dimensional Quantum Turbulence

Cited by 107 publications

References 63 publications

Vortices and vortex lattices in quantum ferrofluids

Vortices and vortex lattices in quantum ferrofluids

Numerical Studies of Quantum Turbulence

Emergence of Order from Turbulence in an Isolated Planar Superfluid

Contact Info

Product

Resources

About