Related papers: Persistent current in a ring coupled to an externa…
The persistent current in small isolated rings enclosing magnetic flux is the current circulating in equilibrium in the absence of an external excitation. While initially studied in superconducting and normal metals, recently, atomic…
The exact solutions of the complete (1+3)-dimensional Dirac equation of fermions moving in ideal Aharonov-Bohm (AB) rings and cylinders are used for deriving the exact expressions of the relativistic partial currents. It is shown that these…
The persistent current in three-dimensional mesoscopic rings is investigated numerically. The model is tight-binding one with random site-energies and interaction between electrons. The self-consistent Hartree-Fock approximation is adopted…
Using the Anderson model in the Kondo regime, we calculate the persistent current j in a ring with an embedded quantum dot (QD) as a function of the Aharonov-Bohm flux Phi for different ring length L, temperature T and broadening of the…
We study the possible stationary persistent supercurrents flowing on a cylindrical sample supporting a two-dimensional charged fluid. The internal dynamics of the fluid is obtained by means of an effective theory in which the fluid…
We study the steady state of a finite XX chain coupled at its boundaries to quantum reservoirs made of free spins that interact one after the other with the chain. The two-point correlations are calculated exactly and it is shown that the…
We develop a dynamic theory of output coupling, for fermionic atoms initially confined in a magnetic trap. We consider an exactly soluble one-dimensional model, with a spatially localized delta-type coupling between the atoms in the trap…
The persistent current, i.e. the equilibrium direct electric current circulating in realistic rings, some authors interpreted as dissipationless in spite of non-zero resistance of the rings, whereas the other one suppose that this current…
The persistent current in three-dimensional mesoscopic rings is investigated numerically. The model is tight-binding one with random site-energies and interaction between electrons. The Hartree-Fock approximation is adopted for the…
In this work, we study persistent current in a mesoscopic cylinder subjected to both longitudinal and transverse magnetic fluxes. A simple tight-binding model is used to describe the system, where all the calculations are performed exactly…
We consider an Aharonov-Bohm interferometer, connected to two electronic reservoirs, with a quantum dot embedded on one of its arms. We find a general expression for the persistent current at steady state, valid for the case where the…
Cooperative effects in oscillator networks are often associated with enhanced stability of phase-locked solutions, which increases with system size. We show that the stabilization of persistent currents in annular atomic superfluids with…
We formalize the parity effect of a multichannel ring coupled to a side branch using the tight binding model. We find that the tight binding model gives slightly different result from the continuum model. We also show that some states of…
For a system of spinless fermions in a disordered mesoscopic ring, interactions can give rise to an enhancement of the persistent current by orders of magnitude. The increase in the current is associated with a charge reorganization of the…
Current enhancement- a novel quantum phenomena is found to occur in a mesoscopic hybrid ring at equilibrium. The hybrid system is described by a ring with bubble which is in turn coupled to a reservoir. In the system the ring encloses a…
Quenching an ultracold bosonic gas in a ring across the Bose-Einstein condensation phase transition is known, and has been experimentally observed, to lead to the spontaneous emergence of persistent currents. The present work examines how…
The tunneling effect of two-dimensional Dirac fermions in a constant magnetic field is studied. This can be done by using the continuity equation at some points to determine the corresponding reflexion and transmission coefficients. For…
A system exhibiting multiple simultaneously broken symmetries offers the opportunity to influence physical phenomena such as tunneling currents by means of external control parameters. Time-reversal symmetry and inversion symmetry are both…
We show that an instability may be present in resonant tunneling through a quantum well in one, two and three dimensions, when the resonance lies near the emitter Fermi level. A simple semiclassical model which simulates the resonance and…
We reconsider the study of persistent currents in a disordered one-dimensional ring threaded by a magnetic flux, using he one-band tight-binding model for a ring of N-sites with random site energies. The secular equation for the…