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arXiv · 1309.1471

Fine structures in the spectrum of the open-boundary Heisenberg chain at large anisotropies

Auditya Sharma·Masudul Haque
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Abstract

At large anisotropies, the spectrum of the Heisenberg XXZ spin chain separates into `bands' with energies largely determined by the number of domain walls. The band structure is richer with open boundary conditions: there are more bands and the bands develop intricate fine structures. We characterize and explain these structures and substructures in the open-boundary chain. The fine structures are explained using degenerate perturbation theory. We also present some dynamical consequences of these sub-band structures, through explicit time evolution of the wavefunction from initial states motivated by the fine structure analysis.

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Auditya Sharma, Masudul Haque. 2013-11-18. Fine structures in the spectrum of the open-boundary Heisenberg chain at large anisotropies. https://doi.org/10.1103/physreva.89.043608

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