Persistent Current in Superconducting Nanorings
Abstract
The superconductivity in very thin rings is suppressed by quantum phase slips. As a result, the amplitude of the persistent current oscillations with flux becomes exponentially small, and their shape changes from sawtooth to a sinusoidal one. We reduce the problem of low-energy properties of a superconducting nanoring to that of a quantum particle in a sinusoidal potential and show that the dependence of the current on the flux belongs to a one-parameter family of functions obtained by solving the respective Schrödinger equation with twisted boundary conditions.
- Publication:
-
Physical Review Letters
- Pub Date:
- August 2002
- DOI:
- 10.1103/PhysRevLett.89.096802
- arXiv:
- arXiv:cond-mat/0207277
- Bibcode:
- 2002PhRvL..89i6802M
- Keywords:
-
- 73.23.Ra;
- 73.63.Nm;
- 74.50.+r;
- Persistent currents;
- Quantum wires;
- Tunneling phenomena;
- point contacts weak links Josephson effects;
- Condensed Matter - Mesoscale and Nanoscale Physics;
- Condensed Matter - Superconductivity
- E-Print:
- 5 pages, 1 figure