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

2020/07/02 by Nemati, Somayyeh, Fumani, Fatemeh Khastehdel, Mahdavifar, Saeed
#FOS: Physical sciences #Quantum Physics (quant-ph)

paper · doi:10.48550/arxiv.2007.01186

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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