Breathers and Raman scattering in a two-leg ladder with staggered Dzyaloshinskii-Moriya interaction

Article

关键词: SINE-GORDON MODEL;    EXACT FORM-FACTORS;    DIMENSIONAL SPIN SYSTEMS;    QUANTUM-FIELD THEORIES;    MAGNETIC-FIELD;    HEISENBERG LADDER;    PHASE-DIAGRAM;    WEAK FERROMAGNETISM;    SINGLET FORMATION;    COPPER BENZOATE;   

DOI  :  10.1103/PhysRevB.76.144422

来源: SCIE

【 摘 要 】

Recent experiments have revealed the role of the staggered Dzyaloshinskii-Moriya interaction in the magnetized phase of an antiferromagnetic spin-1/2 two-leg ladder compound under a uniform magnetic field. We derive a low-energy effective field theory describing a magnetized two-leg ladder with a weak staggered Dzyaloshinskii-Moriya interaction. This theory predicts the persistence of the spin gap in the magnetized phase, in contrast to standard two-leg ladders, and the presence of bound states in the excitation spectrum. Such bound states are observable in Raman scattering measurements. These results are then extended to intermediate Dzyaloshinskii-Moriya interaction using exact diagonalizations.

【 授权许可】

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