Anderson orthogonality catastrophe in $2+1$-D topological systems

Jiahua Gu

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arXiv · 1905.00171

Anderson orthogonality catastrophe in $2+1$-D topological systems

Jiahua Gu

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Abstract

In the thermodynamic limit, a many-body ground state has zero overlap with another state which is a slightly perturbed state of the original one, known as the Anderson orthogonality catastrophe (AOC). The amplitude of the overlap for two generic ground states typically exhibits exponential or power-law decay as the system size increases to infinity. In this paper, we show that for generic $(2+1)$-D topological systems at fixed points, there exists a universal topological response term in the scaling of the ground-state overlap. For Laughlin wave functions, in particular, we also find a leading term decaying faster than exponential, which is beyond AOC. Such finite-size scaling behaviors could be utilized to theoretically detect the gapless edge modes, distinguish the topology of quantum states or serve as a signature for topological phase transitions.

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Jiahua Gu. 2019-05-01. Anderson orthogonality catastrophe in $2+1$-D topological systems. https://arxiv.org/abs/1905.00171

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