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arXiv · 1607.03407

Detecting phase transitions and crossovers in Hubbard models using the fidelity susceptibility

Li Huang·Yilin Wang·Lei Wang·Philipp Werner
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Abstract

A generalized version of the fidelity susceptibility of single-band and multi-orbital Hubbard models is systematically studied using single-site dynamical mean-field theory in combination with a hybridization expansion continuous-time quantum Monte Carlo impurity solver. We find that the fidelity susceptibility is extremely sensitive to changes in the state of the system. It can be used as a numerically inexpensive tool to detect and characterize a broad range of phase transitions and crossovers in Hubbard models, including (orbital-selective) Mott metal-insulator transitions, high-spin to low-spin transitions, Fermi-liquid to non-Fermi-liquid crossovers, and spin-freezing crossovers.

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Li Huang, Yilin Wang, Lei Wang, Philipp Werner. 2016-07-12. Detecting phase transitions and crossovers in Hubbard models using the fidelity susceptibility. https://doi.org/10.1103/physrevb.94.235110

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