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The spin-Peierls chain revisited

Georg Hager·Alexander Weisse·Gerhard Wellein·Eric Jeckelmann·Holger Fehske
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Abstract

We extend previous analytical studies of the ground-state phase diagram of a one-dimensional Heisenberg spin chain coupled to optical phonons, which for increasing spin-lattice coupling undergoes a quantum phase transition from a gap-less to a gaped phase with finite lattice dimerisation. We check the analytical results against established four-block and new two-block density matrix renormalisation group (DMRG) calculations. Different finite-size scaling behaviour of the spin excitation gaps is found in the adiabatic and anti-adiabatic regimes.

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Georg Hager, Alexander Weisse, Gerhard Wellein, Eric Jeckelmann, Holger Fehske. 2006-06-14. The spin-Peierls chain revisited. https://doi.org/10.1016/j.jmmm.2006.10.399

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