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
U2 - 10.1016/S0375-9601(96)00876-6
DO - 10.1016/S0375-9601(96)00876-6
M3 - Article
AN - SCOPUS:0542361197
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 -