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arXiv · 1801.10602

Variational model for one-dimensional quantum magnets

Yu. B. Kudasov·R. V. Kozabaranov
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Abstract

A new variational technique for investigation of the ground state and correlation functions in 1D quantum magnets is proposed. A spin Hamiltonian is reduced to a fermionic representation by the Jordan-Wigner transformation. The ground state is described by a new non-local trial wave function, and the total energy is calculated in an analytic form as a function of two variational parameters. This approach is demonstrated with an example of the XXZ-chain of spin-1/2 under a staggered magnetic field. Generalizations and applications of the variational technique for low-dimensional magnetic systems are discussed.

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Yu. B. Kudasov, R. V. Kozabaranov. 2018-01-31. Variational model for one-dimensional quantum magnets. https://doi.org/10.1016/j.physleta.2018.02.031

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