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arXiv · 1210.3919

On the compressibility of deformable spin chains in a vicinity of quantum critical points

Oleg Derzhko·Jozef Strecka·Lucia Galisova
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Abstract

We calculate the ground-state compressibility of a deformable spin-1/2 Heisenberg-Ising chain with Dzyaloshinskii-Moriya interaction to discuss how a quantum critical point inherent in this spin system may manifest itself in the elastic properties of the underlying lattice. We compare these results with the corresponding ones for the spin-1/2 Ising chain in a longitudinal or transverse field and the spin-1/2 $XX$ chain in a transverse field. The inverse compressibility of the spin-1/2 $XX$ chain in a transverse field exhibits a hysteresis in a vicinity of quantum critical point that is accompanied with the finite jump of compressibility. Contrary to this, the inverse compressibility diminishes continuously close to a quantum critical point of the spin-1/2 Ising chain in a transverse field and the spin-1/2 Heisenberg-Ising bond alternating chain.

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Oleg Derzhko, Jozef Strecka, Lucia Galisova. 2012-10-15. On the compressibility of deformable spin chains in a vicinity of quantum critical points. https://doi.org/10.1140/epjb%2Fe2013-30979-4

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