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Thermodynamic properties of the periodic nonuniform spin-1/2 isotropic XY chains in a transverse field

Oleg Derzhko·Johannes Richter·Oles' Zaburannyi
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Abstract

Using the Jordan-Wigner transformation and the continued-fraction method we calculate exactly the density of states and thermodynamic quantities of the periodic nonuniform spin-1/2 isotropic XY chain in a transverse field. We discuss in detail the changes in the behaviour of the thermodynamic quantities caused by regular nonuniformity. The exact consideration of thermodynamics is extended including a random Lorentzian transverse field. The presented results are used to study the Peierls instability in a quantum spin chain. In particular, we examine the influence of a non-random/random field on the spin-Peierls instability with respect to dimerization.

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Oleg Derzhko, Johannes Richter, Oles' Zaburannyi. 2000-02-09. Thermodynamic properties of the periodic nonuniform spin-1/2 isotropic XY chains in a transverse field. https://doi.org/10.1016/s0378-4371(00)00084-4

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