### Abstract

The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length ξ but much smaller than the Pearl length Λ=2λ2/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 or 180 turns, the zero-field critical current at H=0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.

Original language | English |
---|---|

Article number | 144511 |

Journal | Physical Review B - Condensed Matter and Materials Physics |

Volume | 85 |

Issue number | 14 |

DOIs | |

Publication status | Published - 10 Apr 2012 |

Externally published | Yes |

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### ASJC Scopus subject areas

- Condensed Matter Physics
- Electronic, Optical and Magnetic Materials

### Cite this

*Physical Review B - Condensed Matter and Materials Physics*,

*85*(14), [144511]. https://doi.org/10.1103/PhysRevB.85.144511

**Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits.** / Clem, John R.; Mawatari, Yasunori; Berdiyorov, Golibjon; Peeters, F. M.

Research output: Contribution to journal › Article

*Physical Review B - Condensed Matter and Materials Physics*, vol. 85, no. 14, 144511. https://doi.org/10.1103/PhysRevB.85.144511

}

TY - JOUR

T1 - Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits

AU - Clem, John R.

AU - Mawatari, Yasunori

AU - Berdiyorov, Golibjon

AU - Peeters, F. M.

PY - 2012/4/10

Y1 - 2012/4/10

N2 - The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length ξ but much smaller than the Pearl length Λ=2λ2/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 or 180 turns, the zero-field critical current at H=0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.

AB - The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length ξ but much smaller than the Pearl length Λ=2λ2/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 or 180 turns, the zero-field critical current at H=0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.

UR - http://www.scopus.com/inward/record.url?scp=84860280462&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84860280462&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.85.144511

DO - 10.1103/PhysRevB.85.144511

M3 - Article

AN - SCOPUS:84860280462

VL - 85

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 0163-1829

IS - 14

M1 - 144511

ER -