Related papers: Dynamics of vortex tangle without mutual friction …
The stability properties and splitting dynamics of multiply quantized vortices are the subject of interest in both theoretical and experimental investigations. Going beyond the regime of validity of Gross-Pitaevskii equation (GPE), we study…
Superfluid phase transitions are discussed from a geometrical perspective as envisaged by Onsager. The approach focuses on vortex loops which close to the critical temperature form a fluctuating vortex tangle. As the transition is…
Motivated by the study of cosmological phase transitions, our understanding of the formation of topological defects during spontaneous symmetry-breaking and the associated non-equilibrium field theory has recently changed. Experiments have…
In my research career in the field of quantum turbulence, I have been encouraged by Vinen. In this article, I review my works motivated by him and my joint collaborations with him. Vinen encouraged me in studies on quantum turbulence at…
In recent experiments, the relaxation dynamics of highly oblate, turbulent Bose-Einstein condensates (BECs) was investigated by measuring the vortex decay rates in various sample conditions [Phys. Rev. A $\bf 90$, 063627 (2014)] and,…
Superfluids with strong spatial modulation can be experimentally produced in the area of cold atoms under the influence of optical lattices. Here we address $^{87}$Rb bosons at T=0 K in a flat geometry under the influence of a periodic…
We investigate the phenomenon of the decay of a supercurrent through homogeneous nucleation of vortex-antivortex pairs in a 2-D like superconductor or superfluid by means of a quantum electrodynamics formulation for the decay of the 2-D…
We perform a numerical simulation of the dynamics of quantized vortices produced by coflow in a square channel using the vortex filament model. Unlike the situation in thermal counterflow, where the superfluid velocity $v_{\rm s}$ and…
We perform Monte Carlo studies of vortices in three dimensions in a cylindrical confinement, with uniform and nonuniform density. The former is relevant to rotating 4He, the latter is relevant to a rotating trapped Bose--Einstein…
We present a diffusion Monte Carlo study of a single vortex in two-dimensional superfluid liquid $^4$He within the fixed node approximation. We use both the Feynman phase and an improved phase which includes backflow correlations to model…
We investigate vortex-antivortex pair creation in a supersonically expanding and contracting quasi-2D Bose-Einstein condensate at zero temperature. For sufficiently large amplitude condensate oscillations, pair production provides the…
Reconnections between quantum vortex filaments in presence of trapped particles are investigated using numerical simulations of the Gross--Pitaevskii equation. Particles are described with classical degrees of freedom and modeled as highly…
Critical dynamics of an ultracold Bose gas far from equilibrium is studied in two spatial dimensions. Superfluid turbulence is created by quenching the equilibrium state close to zero temperature. Instead of immediately re-thermalizing, the…
Turbulence, produced by an impulsive spin-down from angular velocity Omega to rest of a cube-shaped container, is investigated in superfluid 4He at temperatures 0.08 K - 1.6 K. The density of quantized vortex lines L is measured by…
The energy spectrum of superfluid turbulence in the absence of the normal fluid is studied numerically. In order to discuss the statistical properties, we calculated the energy spectra of the 3D velocity field induced by dilute and dense…
We study the decay of vortices in Bose-Einstein condensates at finite temperatures by means of the Zaremba Nikuni Griffin formalism, in which the condensate is modelled by a Gross Pitaevskiiequation, which is coupled to a Boltzmann kinetic…
We investigate thermal relaxation of superfluid turbulence in a highly oblate Bose-Einstein condensate. We generate turbulent flow in the condensate by sweeping the center region of the condensate with a repulsive optical potential. The…
Experiments in superfluid 4He show that at low temperatures, energy dissipation from moving vortices is many orders of magnitude larger than expected from mutual friction. Here we investigate other mechanisms for energy loss by a…
Superfluidity is a special state of matter exhibiting macroscopic quantum phenomena and acting like a fluid with zero viscosity. In such a state, superfluid vortices exist as phase singularities of the model equation with unique…
The damping of vortex cyclotron modes is investigated within a generalized quantum theory of vortex waves. Similarly to the case of Kelvin modes, the friction coefficient turns out to be essentially unchanged under such oscillations, but it…