Quantum critical point of the Ising chain from boundary effects

Oskar A. Prośniak

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arXiv · 1810.00983

Quantum critical point of the Ising chain from boundary effects

Oskar A. Prośniak

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Abstract

We propose two easy-to-study observables in the quantum Ising chain with open boundary conditions. They measure the length at which boundaries affect the longitudinal or transverse magnetization. We show that their finite-size scaling behaviour encodes the position of the quantum critical point and the universal scaling exponent $\nu$. The applicability of proposed observables in small systems is also discussed. We expect that our results will be useful in quantum simulation of spin systems.

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Oskar A. Prośniak. 2018-10-01. Quantum critical point of the Ising chain from boundary effects. https://arxiv.org/abs/1810.00983

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