Superfluid Edge Dislocation: Transverse Quantum Fluid.

Recently, it was argued [Kuklov et al., Phys. Rev.

Supertransport by Superclimbing Dislocations in ^{4}He: When All Dimensions Matter.

The unique superflow-through-solid effect observed in solid ^{4}He and attributed to the quasi-one-dimensional superfluidity along the dislocation cores exhibits two extraordinary features: (i) an exponentially strong suppression of the flow by a moderate increase in pressure and (ii) an unusual temperature dependence of the flow rate with no analogy to any known system and in contradiction with the standard Luttinger liquid paradigm. Based on ab initio and model simulations, we argue that the two features are closely related: Thermal fluctuations of the shape of a superclimbing edge dislocation induce large, correlated, and asymmetric stress fields acting on the superfluid core. The critical flux is most sensitive to strong rare fluctuations and hereby acquires a sharp temperature dependence observed in experiments.

Revisiting universality of the liquid-gas critical point in two dimensions.

Critical point of liquid-gas (LG) transition does not conform with the paradigm of spontaneous symmetry breaking because there is no broken symmetry in both phases. We revisit the conjecture that this critical point belongs to the Ising class by performing large scale Monte Carlo simulations in two-dimensional free space in combination with the numerical flowgram method. Our main result is that the critical indices do agree with the Onsager values within the error of 1%-2%.

Topological quantum phases of 4He confined to nanoporous materials.

The ground state of (4)He confined in a system with the topology of cylinder can display properties of solid, superfluid, and liquid crystal. This phase, which we call a compactified supersolid (CSS), originates from wrapping the basal planes of the bulk hcp solid into concentric cylindrical shells, with several central shells exhibiting superfluidity along the axial direction. Its main feature is the presence of a topological defect which can be viewed as a disclination with Frank index n = 1 observed in liquid crystals, and which, in addition, has a superfluid core.