### Abstract

Chiral order of the Josephson-junction ladder with half a flux quantum per plaquette is studied by means of the exact diagonalization method. We consider an extreme quantum limit where each superconductor grain (order parameter) is represented by S = 1/2 spin. So far, the semi-classical S → ∞ case, where each spin reduces to a plane rotator, has been considered extensively. We found that in the case of S = 1/2, owing to the strong quantum fluctuations, the chiral (vortex lattice) order becomes dissolved except in a region, where attractive intrachain and, to our surprise, repulsive interchain interactions both exist. On the contrary, for considerably wide range of parameters, the superconductor (XY) order is kept critical. The present results are regarded as a demonstration of the critical phase accompanying chiral-symmetry breaking predicted for frustrated XXZ chain field-theoretically.

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

Pages (from-to) | 295-299 |

Number of pages | 5 |

Journal | European Physical Journal B |

Volume | 17 |

Issue number | 2 |

Publication status | Published - Sep 2 2000 |

### Fingerprint

### Keywords

- 75.10.Jm Quantized spin models
- 75.40.Mg Numerical simulation studies
- 85.25.Cp Josephson devices

### ASJC Scopus subject areas

- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics

### Cite this

**Finite-size-scaling analyses of the chiral order in the Josephson-junction ladder with half a flux quantum per plaquette.** / Nishiyama, Yoshihiro.

Research output: Contribution to journal › Article

*European Physical Journal B*, vol. 17, no. 2, pp. 295-299.

}

TY - JOUR

T1 - Finite-size-scaling analyses of the chiral order in the Josephson-junction ladder with half a flux quantum per plaquette

AU - Nishiyama, Yoshihiro

PY - 2000/9/2

Y1 - 2000/9/2

N2 - Chiral order of the Josephson-junction ladder with half a flux quantum per plaquette is studied by means of the exact diagonalization method. We consider an extreme quantum limit where each superconductor grain (order parameter) is represented by S = 1/2 spin. So far, the semi-classical S → ∞ case, where each spin reduces to a plane rotator, has been considered extensively. We found that in the case of S = 1/2, owing to the strong quantum fluctuations, the chiral (vortex lattice) order becomes dissolved except in a region, where attractive intrachain and, to our surprise, repulsive interchain interactions both exist. On the contrary, for considerably wide range of parameters, the superconductor (XY) order is kept critical. The present results are regarded as a demonstration of the critical phase accompanying chiral-symmetry breaking predicted for frustrated XXZ chain field-theoretically.

AB - Chiral order of the Josephson-junction ladder with half a flux quantum per plaquette is studied by means of the exact diagonalization method. We consider an extreme quantum limit where each superconductor grain (order parameter) is represented by S = 1/2 spin. So far, the semi-classical S → ∞ case, where each spin reduces to a plane rotator, has been considered extensively. We found that in the case of S = 1/2, owing to the strong quantum fluctuations, the chiral (vortex lattice) order becomes dissolved except in a region, where attractive intrachain and, to our surprise, repulsive interchain interactions both exist. On the contrary, for considerably wide range of parameters, the superconductor (XY) order is kept critical. The present results are regarded as a demonstration of the critical phase accompanying chiral-symmetry breaking predicted for frustrated XXZ chain field-theoretically.

KW - 75.10.Jm Quantized spin models

KW - 75.40.Mg Numerical simulation studies

KW - 85.25.Cp Josephson devices

UR - http://www.scopus.com/inward/record.url?scp=0001247221&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001247221&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0001247221

VL - 17

SP - 295

EP - 299

JO - European Physical Journal B

JF - European Physical Journal B

SN - 1434-6028

IS - 2

ER -