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arXiv:1810.00983

Quantum critical point of the Ising chain from boundary effects

Oskar Amadeusz Prośniak

Published Oct 1, 2018• 0 citations
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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 $ν$. 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.

DOI
10.48550/arxiv.1810.00983

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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 ννν. 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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