Ground state fidelity and quantum phase transitions in free Fermi systems
P. Zanardi, M. Cozzini, P. Giorda
Abstract
We compute the fidelity between the ground states of general quadratic fermionic hamiltonians and analyze its connections with quantum phase transitions. Each of these systems is characterized by a L× L real matrix whose polar decomposition, into a non-negative Λ and a unitary T, contains all the relevant ground state (GS) information. The boundaries between different regions in the GS phase diagram are given by the points of, possibly asymptotic, singularity of Λ. This latter in turn implies a critical drop of the fidelity function. We present general results as well as their exemplification by a model of fermions on a totally connected graph.
Create a lesson
Related papers
Spectral Fingerprints of Gauge Theories on a Quantum Computer
Graham Van Goffrier, Debasish Banerjee, Bipasha Chakraborty et al.
Dynamics of local quantum information in random unitary circuits
Ratul Thakur, Sthitadhi Roy
Factorized Boolean representations for efficient quantum synthesis
Mehul Shah, Robert Fiszer, Marek Perkowski
Detuning- and Stark-robust Rydberg gates
Elie Bataille, Gyohei Nomura, Manuel Endres
Krylov Break Times from an Inhomogeneous Lieb--Robinson Light Cone
Shunji Matsuura, Yoji Kawamura, Joseph Salfi et al.
Stochastic transport of a Goldstone mode in a self-organized atomic crystal
Zhanhai Yu, Di Xiang, Xiaotian Zhang et al.