Hartree-Fock Simulation of Persistent Current in Rings with Single Scatterer

Persistent Current of Interacting Electrons: a Simple Hartree-Fock Picture

The average persistent current (Ii of diffusive electrons in trie Hartree-Fock

Persistent current for interacting electrons: a simple Hartree-Fock picture

The average persistent current 〈I〉 of diffusive electrons in the Hartree-Fock approximation is derived in a simple non-diagrammatic picture. The Fourier expansion directly reflects the winding number decomposition of the diffusive motion around the ring. One recovers the results of Ambegaokar and Eckern, and Schmid. Moreover one finds an expression for 〈I〉 which is valid beyond the diffusive re...

Random Walk Beyond Hartree - Fock

We give a brief discussion of the recently developed Constrained-Path Monte Carlo Method. This method is a quantum Monte Carlo technique that eliminates the fermion sign problem plaguing simulations of systems of interacting electrons. The elimination is accomplished by trading an exact procedure for an approximate one that has been demonstrated to give very accurate estimates of energies and m...

Persistent Current in Metallic Rings and Cylinders

Persistent current in small superconducting rings.

We study theoretically the contribution of fluctuating Cooper pairs to the persistent current in superconducting rings threaded by a magnetic flux. For sufficiently small rings, in which the coherence length xi exceeds the radius R, mean field theory predicts a full reduction of the transition temperature to zero near half-integer flux. We find that nevertheless a very large current is expected...