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View article: Topological transport of a classical droplet in a lattice of time
Topological transport of a classical droplet in a lattice of time Open
Thouless charge pumps are quantum mechanical devices whose operation relies on topology. They provide the means for transporting quantum matter in space lattices with a single quantum precision. Contrasting space crystals that spontaneousl…
View article: Topological transport of a classical droplet in a lattice of time
Topological transport of a classical droplet in a lattice of time Open
Thouless charge pumps are quantum mechanical devices whose operation relies on topology. They provide the means for transporting quantum matter in space lattices with a single quantum precision. Contrasting space crystals that spontaneousl…
View article: Quantum double structure in cold atom superfluids
Quantum double structure in cold atom superfluids Open
The theory of topological quantum computation is underpinned by two important classes of models. One is based on non-abelian Chern-Simons theory, which yields the so-called $\rm{SU}(2)_k$ anyon models that often appear in the context of el…
View article: Quantum double structure in cold atom superfluids
Quantum double structure in cold atom superfluids Open
The theory of topological quantum computation is underpinned by two important classes of models. One is based on non-abelian Chern–Simons theory, which yields the so-called SU(2)k anyon models that often appear in the context of electrical…
View article: Fluctuation theorem anomaly in a point-vortex fluid
Fluctuation theorem anomaly in a point-vortex fluid Open
The second law of thermodynamics posits that in closed macroscopic systems the rate of entropy production must be positive. However, small systems can exhibit negative entropy production over short timescales, seemingly in contradiction wi…
View article: Vortex spin in a superfluid
Vortex spin in a superfluid Open
General relativity predicts that the curvature of spacetime induces spin rotations on a parallel transported particle. We deploy Unruh's analogue gravity picture and consider a quantised vortex embedded in a two-dimensional superfluid Bose…
View article: Topological quantum computation using analog gravitational holonomy and time dilation
Topological quantum computation using analog gravitational holonomy and time dilation Open
Non-universal topological quantum computation models, such as the Majorana fermion-based Ising anyon model, have to be supplemented with an additional non-topological noisy gate in order to achieve universality. Here we endeavour to remedy…
View article: Droplet time crystals
Droplet time crystals Open
We have constructed and characterised an instrument to study gravitationally bouncing droplets of fluid, subjected to periodic driving force. Our system incorporates a droplet printer that enables an on-demand computer controlled depositio…
View article: Report on scipost_202206_00002v1
Report on scipost_202206_00002v1 Open
Non-universal topological quantum computation models, such as the Majorana fermionbased Ising anyon model, have to be supplemented with an additional non-topological noisy gate in order to achieve universality.Here we endeavour to remedy t…
View article: Machine-learning classification of two-dimensional vortex configurations
Machine-learning classification of two-dimensional vortex configurations Open
We consider computer generated configurations of quantised vortices in planar\nsuperfluid Bose-Einstein condensates. We show that unsupervised machine\nlearning technology can successfully be used for classifying such vortex\nconfiguration…
View article: Numerical Simulations of a Superwalking Droplet
Numerical Simulations of a Superwalking Droplet Open
A new class of walking droplets, coined superwalkers, has been observed when a bath of silicone oil is vibrated simultaneously at a given frequency and its subharmonic tone with a relative phase difference between them~[1]. In this paper, …
View article: Liquid Time Crystals
Liquid Time Crystals Open
We have constructed and characterised an instrument to study gravitationally bouncing droplets of fluid, subjected to periodic driving force. Our system incorporates a droplet printer that enables an on-demand computer controlled depositio…
View article: Two Nambu-Goldstone zero modes for rotating Bose-Einstein condensates
Two Nambu-Goldstone zero modes for rotating Bose-Einstein condensates Open
We consider rotating finite size vortex arrays in Bose-Einstein condensates\nthat are confined by cylindrically symmetric external potentials. We show that\nsuch systems possess two exact Nambu-Goldstone zero modes associated with two\nspo…
View article: Geometric phases of a vortex in a superfluid
Geometric phases of a vortex in a superfluid Open
We consider geometric phases of mobile quantum vortices in superfluid Bose-Einstein condensates. Haldane and Wu [Phys. Rev. Lett. 55, 2887 (1985)] showed that the geometric phase, $γ_{\mathcal C}=2πN_{\mathcal C}$, of such a vortex is dete…
View article: Unsteady dynamics of a classical particle-wave entity
Unsteady dynamics of a classical particle-wave entity Open
A droplet bouncing on the surface of a vertically vibrating liquid bath can walk horizontally, guided by the waves it generates on each impact. This results in a self-propelled classical particle-wave entity. By using a one-dimensional the…
View article: Stop-and-go locomotion of superwalking droplets
Stop-and-go locomotion of superwalking droplets Open
Vertically vibrating a liquid bath at two frequencies, f and f/2, having a constant relative phase difference can give rise to self-propelled superwalking droplets on the liquid surface. We have numerically investigated such superwalking d…
View article: Fibonacci anyons versus Majorana fermions
Fibonacci anyons versus Majorana fermions Open
We have studied ${\rm SU}(2)_k$ anyon models, assessing their prospects for topological quantum computation. In particular, we have compared the Ising ($k=2$) anyon and Fibonacci ($k=3$) anyon models, motivated by their potential for futur…
View article: Gravitational vortex mass in a superfluid
Gravitational vortex mass in a superfluid Open
We consider superfluid hydrodynamics of two-dimensional Bose-Einstein condensates. Interpreting the curvature of the macroscopic condensate wave function as an effective gravity in such a superfluid universe, we argue for a superfluid equi…
View article: Braiding and Fusion of Non-Abelian Vortex Anyons
Braiding and Fusion of Non-Abelian Vortex Anyons Open
We have studied topology and dynamics of quantum vortices in spin-2 Bose-Einstein condensates. By computationally modeling controllable braiding and fusion of these vortices, we have demonstrated that certain vortices in such spinor conden…
View article: Superwalking Droplets
Superwalking Droplets Open
A walker is a droplet of liquid that self-propels on the free surface of an oscillating bath of the same liquid through feedback between the droplet and its wave field. We have studied walking droplets in the presence of two driving freque…
View article: Report on 1903.05528v1
Report on 1903.05528v1 Open
We numerically model decaying quantum turbulence in two-dimensional disk-shaped Bose-Einstein condensates, and investigate the effects of finite temperature on the turbulent dynamics.We prepare initial states with a range of condensate tem…
View article: Report on 1903.05528v1
Report on 1903.05528v1 Open
We numerically model decaying quantum turbulence in two-dimensional disk-shaped Bose-Einstein condensates, and investigate the effects of finite temperature on the turbulent dynamics.We prepare initial states with a range of condensate tem…
View article: Order from chaos: Observation of large-scale flow from turbulence in a two-dimensional superfluid
Order from chaos: Observation of large-scale flow from turbulence in a two-dimensional superfluid Open
Interacting systems driven far from equilibrium tend to evolve to steady states exhibiting large-scale structure and order. In two-dimensional turbulent flow the seemingly random swirling motion of a fluid can evolve towards persistent lar…
View article: Hong–Ou–Mandel-like two-droplet correlations
Hong–Ou–Mandel-like two-droplet correlations Open
We present a numerical study of two-droplet pair correlations for in-phase droplets walking on a vibrating bath. Two such walkers are launched toward a common point of intersection. As they approach, their carrier waves may overlap and the…
View article: Classical simulation of a topological quantum computer
Classical simulation of a topological quantum computer Open
Topological quantum computers promise a fault tolerant means to perform quantum computation. Topological quantum computers use particles with exotic exchange statistics called non-Abelian anyons, and the simplest anyon model which allows f…
View article: Motion of vortices in inhomogeneous Bose-Einstein condensates
Motion of vortices in inhomogeneous Bose-Einstein condensates Open
We derive a general and exact equation of motion for a quantised vortex in an\ninhomogeneous two-dimensional Bose-Einstein condensate. This equation expresses\nthe velocity of a vortex as a sum of local ambient density and phase gradients\…
View article: Vortex mass in a superfluid
Vortex mass in a superfluid Open
We consider the inertial mass of a vortex in a superfluid. We obtain a vortex\nmass that is well defined and is determined microscopically and\nself-consistently by the elementary excitation energy of the kelvon\nquasiparticle localised wi…