In samples used to maintain the US resistance standard the breakdown of the dissipationless integer quantum Hall effect occurs as a series of dissipative voltage steps. A mechanism for this type of breakdown is proposed, based on the generation of magneto-excitons when the quantum Hall fluid flows past an ionised impurity above a critical velocity. The calculated generation rate gives a voltage...

We show that a Bose-condensed gas, under extreme rotation in a 2D anisotropic trap, forms a novel elongated quantum fluid which has a roton-maxon excitation spectrum. For a sufficiently large interaction strength, the roton energy reaches zero and the system undergoes a second order quantum transition to the state with a periodic structure-rows of vortices. The number of rows increases with the...

Using a new version of the density-matrix renormalization group we determine the phase diagram of a model of an antiferromagnetic Heisenberg spin chain where the spins interact with quantum phonons. A quantum phase transition from a gapless spin-fluid state to a gapped dimerized phase occurs at a nonzero value of the spin-phonon coupling. The transition is in the same universality class as that...

We investigate the validity of stationary simulations for semiconductor quantum charge transport in a one-dimensional resonant tunneling diode via fluid type models. Careful numerical investigations to a quantum hydrodynamic model reveal that the transient simulations do not always converge to the steady states. In particular, growing oscillations are observed at relatively large applied voltag...

Borelli et.al. [Phys. Lett. A 267 (2000) 201] study a 2-dimensional fluid membrane in a 2+1-dimensional space, subject to quantum fluctuations. Unfortunately, they use an unphysical kinetic-energy term which is not invariant under coordinate transformations. Moreover, they expand the resulting field theory around D = 2, which is not its lower critical dimension. We study the corrected field the...

In present paper we construct the classical and minisuperspace quantum models of an extended charged particle. The modelling is based on the radiation fluid singular hypersurface filled with physical vacuum. We demonstrate that both at classical and quantum levels such a model can have equilibrium states at the radius equal to the classical radius of a charged particle. In the cosmological cont...

It occurs that when we attempt to melt the nucleon in order to obtain the free quark gas, or QGP fluid the mass of the heat quantum (heaton) is equal to the π−meson mass.

In this paper we develop high order asymptotic preserving methods for the spatially inhomogeneous quantum Boltzmann equation. We follow the work in Li and Pareschi [18] where asymptotic preserving exponential Runge-Kutta methods for the classical inhomogeneous Boltzmann equation were constructed. A major difficulty here is related to the non Gaussian steady states characterizing the quantum kin...

As an application of quantum fluid mechanics, we consider the drag force exerted on a sphere by an ultradilute gas. Quantum mechanical diffraction scattering theory enters in that regime wherein the mean free path of a molecule in the gas is large compared with the sphere radius. The drag force is computed in a model specified by the "sticking fraction" of events in which a gaseous molecule is ...