Multi-particle excitations and spectral densities in quantum spin-systems
arXiv:cond-mat/0107526 · doi:10.1016/S0921-4526(01)01333-3
Abstract
The excitation spectrum of the 2-leg S=1/2 Heisenberg ladder is examined perturbatively. Using an optimally chosen continuous unitary transformation we expand the Hamiltonian and the Raman operator about the limit of isolated rungs leading to high order series expansions allowing to calculate spectral densities quantitatively. The 2-particle sector is examined for total momentum k=0. We show that triplet-triplet interaction gives rise to a band splitting.
2 pages, 1 figure; submitted to the proceedings of the SCES2001 conference (Physica B)
References in corpus (1)
Cited by in corpus (5)
- Excitations in one-dimensional S=1/2 quantum antiferromagnets
- The Structure of Operators in Effective Particle-Conserving Models
- Derivation of the t-J model for finite doping
- Boundaries, Cusps and Caustics in the Multimagnon Continua of 1D Quantum Spin Systems
- Magnetic excitations in two-leg spin 1/2 ladders: experiment and theory