Fidelity approach: the misleading role of finite size level crossing of excited energies

Somayyeh Nemati; Fatemeh Khastehdel Fumani; Saeed Mahdavifar

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arXiv · 2007.01186

Fidelity approach: the misleading role of finite size level crossing of excited energies

Somayyeh Nemati·Fatemeh Khastehdel Fumani·Saeed Mahdavifar

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Abstract

Here, we show that, although quantum fidelity can truly identify two quantum phase transitions of a one-dimensional spin-1/2 quantum Ising model with competing nearest and next-nearest neighbour interactions in a transverse magnetic field, it may not be a suitable approach for analyzing its ground-state phase diagram.

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Somayyeh Nemati, Fatemeh Khastehdel Fumani, Saeed Mahdavifar. 2020-07-02. Fidelity approach: the misleading role of finite size level crossing of excited energies. https://arxiv.org/abs/2007.01186

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