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arXiv · 2405.10230

Universal entanglement correction induced by relevant deformations at the quantum critical point

Rui-Zhen Huang·Chen Peng
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Abstract

Local relevant deformations are important tool to study universal properties of quantum critical points. We investigate the effect of small relevant deformations on the bi-partite entanglement entropy at the quantum critical points. Within the quantum critical region, a universal power-law correction in the entanglement entropy induced by the relevant operator is found in both one- and two-dimensional critical lattice models. The exponent of the power-law correction term is determined by the scaling dimension of the relevant operator. Based on numerical simulations and scaling theory argument, it is conjectured that such a universal power-law correction in the entanglement entropy is universal for Lorentz invariant quantum critical points. Without Lorentz invariance, it is found the exponent in the power-law correction term does not fit in with the scaling argument in models with a dynamical exponent z=2 in two dimension. This may be because the relevant operator added in the lattice model corresponds to complicated operators in the corresponding conformal field theory. Our study provides a different perspective to extract universal information of quantum critical points. We expect it would be useful to detect unique properties of topological quantum phase transitions.

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Rui-Zhen Huang, Chen Peng. 2024-05-16. Universal entanglement correction induced by relevant deformations at the quantum critical point. https://doi.org/10.1103/lwsj-q4th

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