Quantum phase slips in a confined geometry

Quantum phase slips in a confined geometry

Decay of Superflow Confined in Thin Torus: Quantum Nucleation of Phase Slips

The quantum nucleation of phase slips in neutral superfluids confined in a thin torus is investigated by means of the collective coordinate method. We have devised, with numerical justification, a certain collective coordinate to describe the quantum nucleation process of a phase slip. Considering the quantum fluctuation around the local minimum of the action, we calculate the effective mass of...

Quantum phase slips in superconducting nanowires.

We have measured the resistance vs temperature of more than 20 superconducting nanowires with nominal widths ranging from 10 to 22 nm and lengths from 100 nm to 1 microm. With decreasing cross-sectional areas, the wires display increasingly broad resistive transitions. The data are in very good agreement with a model that includes both thermally activated phase slips close to T(c) and quantum p...

Quantum phase slips in Josephson junction rings

G. Rastelli,1,2 I. M. Pop,3,4 and F. W. J. Hekking1 1Université Grenoble 1/CNRS, LPMMC UMR 5493, B.P. 166, 38042 Grenoble, France 2Fachbereich Physik, Universität Konstanz, D-78457 Konstanz, Germany 3Institut Néel, CNRS, and Université Joseph Fourier, B.P. 166, 38042 Grenoble, France 4Department of Applied Physics, Yale University, New Haven, Connecticut 06511, USA (Received 6 January 2012; rev...

Tunable spin gaps in a quantum-confined geometry.

We have studied the interplay of a giant spin-orbit splitting and of quantum confinement in artificial Bi-Ag-Si trilayer structures. Angle-resolved photoelectron spectroscopy reveals the formation of a complex spin-dependent gap structure, which can be tuned by varying the thickness of the Ag buffer layer. This provides a means to tailor the electronic structure at the Fermi energy, with potent...