### Abstract

We consider the instability of the ground state of the Δ chain against a lattice distortion increasing the bond strength (λ) in each triangle. It relaxes the frustration and causes a remarkable gap enhancement; only a 6% increase of λ doubles the gap compared to the fully-frustrated case (λ = 1). The lowest excitation is revealed to be a kink-antikink bound state whose correlation length decreases drastically with λ increase. The enhancement follows a power law, ΔE_{gap} ∼ (λ - 1) + 1.44(λ - 1)^{2/3}, which can be obtained from the exact result of the continuum model.

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

Pages (from-to) | 315-320 |

Number of pages | 6 |

Journal | Physics Letters, Section A: General, Atomic and Solid State Physics |

Volume | 225 |

Issue number | 4-6 |

Publication status | Published - 1997 Feb 3 |

Externally published | Yes |

### Fingerprint

### Keywords

- Frustrated quantum spin chain
- Spin gap

### ASJC Scopus subject areas

- Physics and Astronomy(all)

### Cite this

*Physics Letters, Section A: General, Atomic and Solid State Physics*,

*225*(4-6), 315-320.

**Relaxation of frustration and gap enhancement by the lattice distortion in the Δ chain.** / Nakamura, Tota; Takada, Satoshi.

Research output: Contribution to journal › Article

*Physics Letters, Section A: General, Atomic and Solid State Physics*, vol. 225, no. 4-6, pp. 315-320.

}

TY - JOUR

T1 - Relaxation of frustration and gap enhancement by the lattice distortion in the Δ chain

AU - Nakamura, Tota

AU - Takada, Satoshi

PY - 1997/2/3

Y1 - 1997/2/3

N2 - We consider the instability of the ground state of the Δ chain against a lattice distortion increasing the bond strength (λ) in each triangle. It relaxes the frustration and causes a remarkable gap enhancement; only a 6% increase of λ doubles the gap compared to the fully-frustrated case (λ = 1). The lowest excitation is revealed to be a kink-antikink bound state whose correlation length decreases drastically with λ increase. The enhancement follows a power law, ΔEgap ∼ (λ - 1) + 1.44(λ - 1)2/3, which can be obtained from the exact result of the continuum model.

AB - We consider the instability of the ground state of the Δ chain against a lattice distortion increasing the bond strength (λ) in each triangle. It relaxes the frustration and causes a remarkable gap enhancement; only a 6% increase of λ doubles the gap compared to the fully-frustrated case (λ = 1). The lowest excitation is revealed to be a kink-antikink bound state whose correlation length decreases drastically with λ increase. The enhancement follows a power law, ΔEgap ∼ (λ - 1) + 1.44(λ - 1)2/3, which can be obtained from the exact result of the continuum model.

KW - Frustrated quantum spin chain

KW - Spin gap

UR - http://www.scopus.com/inward/record.url?scp=0542361197&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0542361197&partnerID=8YFLogxK

M3 - Article

VL - 225

SP - 315

EP - 320

JO - Physics Letters, Section A: General, Atomic and Solid State Physics

JF - Physics Letters, Section A: General, Atomic and Solid State Physics

SN - 0375-9601

IS - 4-6

ER -