Fidelity, dynamic structure factor, and susceptibility in critical phenomena.
Motivated by the growing importance of fidelity in quantum critical phenomena, we establish a general relation between the fidelity and structure factor of the driving term in a Hamiltonian through the concept of fidelity susceptibility. Our discovery, as shown by some examples, facilitates the evaluation of fidelity in terms of susceptibility using well-developed techniques, such as density matrix renormalization group for the ground state, or Monte Carlo simulations for the states in thermal equilibrium.
You
Wen-Long
WL
Department of Physics and Institute of Theoretical Physics, The Chinese University of Hong Kong, Hong Kong, China.
Li
Ying-Wai
YW
Gu
Shi-Jian
SJ