We introduce the concepts of Berezinskii-Kosterlitz-Thouless (BKT) transition and quasi longrange order in the context of the 2D electron gas model. We then apply this framework to 2D superfluidity to obtain the superfluid transition temperature. Finally, we review the recent experimental work of Hadzibabic et al. which observes BKT transition in a 2D trapped Rb gas. Thermal de Broglie waveleng...

We study the superfluid to Mott-insulator transition of bosons in an optical anizotropic lattice by employing the Bose-Hubbard model living on a two-dimensional lattice with anizotropy parameter κ. The compressible superfluid state and incompressible Mott-insulator (MI) lobes are efficiently described analytically, using the quantum U(1) rotor approach. The ground state phase diagram showing th...

To realize a non-Abelian s-wave topological superfluid of cold Fermi gases, generally a Zeeman energy splitting larger than the superfluid pairing gap is necessary. In this paper, we find that using an anisotropic and spin-dependent optical lattice to trap gases, a new non-Abelian topological superfluid phase appears, in contrast to an isotropic and spin-independent optical lattice. A character...

We study the superfluid transition of 4He in aerogel by Monte Carlo simulations and finite size scaling analysis. Aerogel is a highly porous silica glass, which we model by a diffusion limited cluster aggregation model. The superfluid is modeled by a three dimensional XY model, with excluded bonds to sites on the aerogel cluster. We obtain the correlation length exponent nu=0.73+/-0.02, in reas...

The Large Hadron Collider (LHC) will be the next particle accelerator built to serve the world's high-energy physics community at CERN, the European Organisation for Nuclear Research. Reusing the 26.7-km circumference tunnel and infrastructure of the existing LEP collider, the LHC will make use of advanced technology high-field superconducting magnets operated in superfluid helium to push the e...

We review the role of strong electronic correlations in quasi–twodimensional organic charge transfer salts such as (BEDT-TTF)2X, (BETS)2Y and β′-[Pd(dmit)2]2Z. We begin by defining minimal models for these materials. It is necessary to identify two classes of material: the first class is strongly dimerised and is described by a half-filled Hubbard model; the second class is not strongly dimeris...

We have investigated the superfluid properties of a ring of weakly interacting and degenerate 1D Bose gas at thermal equilibrium with a rotating vessel. The conventional definition of superfluidity predicts that the gas has a significant superfluid fraction only in the Bose condensed regime. In the opposite regime, it is found that a superfluid behaviour can still be identified when the probabi...

K. Matsumoto,* J. V. Porto, L. Pollack, E. N. Smith, T. L. Ho, and J. M. Parpia Laboratory of Atomic & Solid State Physics and Materials Science Center, Cornell University, Ithaca, New York 14853 (Received 14 January 1997) We present evidence for a nonzero pressure, T ­ 0 superfluid phase transition of 3He in 98.2% open aerogel. Unlike bulk 3He which is a superfluid at T ­ 0 at all pressures (d...

N. Mulders Department of Physics and Astronomy, University of Delaware, 223 Sharp Laboratory, Newark, Delaware 19716 (Received 21 December 1998) Liquid 3He in 98%-porous aerogel simultaneously possesses properties of a disordered p-wave superfluid and an elastic solid. We have observed two sound modes of superfluid 3He in aerogel. The first (fast) sound is a compression wave, and the second (sl...

The physics of graphene and of the superfluid phases of 3He have many common features. Both systems are topological materials where quasiparticles behave as relativistic massless (Weyl, Majorana or Dirac) fermions. We formulate the points where these features are overlapping. This will allow us to use graphene to study the properties of superfluid 3He, to use superfluid 3He to study the propert...