Related papers: Quantized vortex rings in superfluid He4 and Light…
The theory of elastic light scattering by semiconductor quantum dots is suggested. The semiclassical method, applying retarded potentials to avoid the problem of bounder conditions for electric and magnetic field, is used. The exact results…
One of the most sought-after objects in topological quantum matter systems is a vortex carrying half a quantum of circulation. They were originally predicted to exist in superfluid 3He-A, but have never been resolved there. Here we report…
A density functional theory is used to investigate the instability arising in superfluid $^4$He as it flows at velocity u just above the Landau critical velocity of rotons v_c. Confirming an early theoretical prediction by one of us [JETP…
The spin of the neutron allows neutron scattering to reveal the magnetic structure and dynamics of materials over nanometre length scales and picosecond timescales. Neutron scattering is particularly in demand in order to understand…
We study theoretically the dynamics of charged quantized vortices (CQVs). CQVs (ion-vortex complexes) have been used as an important probe in the field of quantum hydrodynamics. Recent experimental studies of quantum turbulence at very low…
Streamlines, vortex lines and magnetic flux tubes in turbulent fluids and plasmas display a great amount of coiling, twisting and linking, raising the question as to whether their topological complexity (continually created and destroyed by…
We propose a new model for the nature of the nucleation of solid from the superfluid phases of $^4$He and $^3$He. Unique to the superfluid phases the solid nucleation involves an extremely fast solidification front. This results in a local…
We investigate the coupled dynamics of quantized vortices and normal fluid in superfluid $^4$He at finite temperatures using a numerical approach based on the vortex filament model (VFM) and lattice Boltzmann method (LBM). The LBM allows us…
In a cold atom gas subject to a 2D spin-dependent optical lattice potential with hexagonal symmetry, trapped atoms undergo orbital motion around the potential minima. Such atoms are elementary quantum rotors. We develop the theory of such…
Nonpolar atoms or molecules with low particle mass and weak inter-particle interactions can form quantum liquids and solids (QLS) at low temperatures. Excess electrons naturally bind to the surfaces of QLS in a vacuum, exhibiting unique…
Using density functional theory, we investigate the structure of mixed $^3$He$_{N_3}$-$^4$He$_{N_4}$ droplets with an embedded impurity (Xe atom or HCN molecule) which pins a quantized vortex line. We find that the…
Vortices are topological defects associated with superfluids and superconductors, which, when mobile, dissipate energy destroying the dissipation-less nature of the superfluid. The nature of this "quantum dissipation" is rooted in the…
We investigate hitherto unexplored regimes of probe scattering by atoms trapped in optical lattices: weak scattering by effectively random atomic density distributions and multiple scattering by arbitrary atomic distributions. Both regimes…
The fact, that $^4$He atoms on different concentric circular paths around the axis of a quantum vortex move with identically equal angular momentum, which represents an important aspect of superfluidity of He-II, has been used to discover a…
A recent experiment has confirmed the existence of quantized turbulence in superfluid He3-B and suggested that turbulence is inhomogenous and spreads away from the region around the vibrating wire where it is created. To interpret the…
We explore the possibility of using superfluid helium for direct detection of sub-GeV dark matter (DM). We discuss the relevant phenomenology resulting from the scattering of an incident dark matter particle on a Helium nucleus. Rather than…
We propose a new theoretical approach to the excitation spectrum of superfluid ${^4}He$. It is based on the assumption that, in addition to the usual Feynman density fluctuations, there exist localized modes which describe the short range…
By combining experiments and numerical simulations which model the dynamics of shaken atomic Bose-Einstein condensates, we reveal the surprising nature of quantum turbulence in these systems. Unlike the tangles of vortex lines described in…
Superfluid $^3$He-B in the zero-temperature limit offers a unique means of studying quantum turbulence by the Andreev reflection of quasiparticle excitations by the vortex flow fields. We validate the experimental visualization of…
We use Super-K data to place new strong limits on interactions of sub-GeV Dark Matter (DM) with nuclei, that rely on the DM flux inevitably induced by cosmic-ray upscatterings. We derive analogous sensitivities at Hyper-K and DUNE and…