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arXiv · 1012.0472

Connecting distant ends of one-dimensional critical systems by a sine-square deformation

Abstract

We study the one-dimensional quantum critical spin systems with the sine-square deformation, in which the energy scale in the Hamiltonian at the position $x$ is modified by the function $f_x = \sin^2\left[π{L}(x-1/2)]$, where $L$ is the length of the system. By investigating the entanglement entropy, spin correlation functions, and wave-function overlap, we show that the sine-square deformation changes the topology of the geometrical connection of the ground state drastically; Although the system apparently has open edges, the sine-square deformation links those ends and realizes the periodic ground state at the level of wave function. Our results propose a new method to control the topology of quantum states by energy-scale deformation.

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BibTeXRIS

Toshiya Hikihara, Tomotoshi Nishino. 2011-02-13. Connecting distant ends of one-dimensional critical systems by a sine-square deformation. https://doi.org/10.1103/physrevb.83.060414

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