Now showing items 1-10 of 449
Sensitivity to perturbations and quantum phase transition
(Amer Physical Soc, 2013-05-17)
The local density of states or its Fourier transform, usually called fidelity amplitude, are important measures of quantum irreversibility due to imperfect evolution. In this Rapid Communication we study both quantities ...
Thermal phase transition for some spin-boson models
In this work we study two different spin-boson models. Such models are generalizations of the Dicke model, it means they describe systems of N identical two-level atoms coupled to a single-mode quantized bosonic field, ...
Nonequilibrium quantum phase transitions in the XY model: comparison of unitary time evolution and reduced density operator approaches
(IOP Publishing, 2014)
We study nonequilibrium quantum phase transitions in the XY spin 1/2 chain using the C* algebra. We show that the well-known quantum phase transition at a magnetic field of h = 1 also persists in the nonequilibrium setting ...
Adiabatic quantum games and phase-transition-like behavior between optimal strategies
In this paper we propose a game of a single qubit whose strategies can be implemented adiabatically. In addition, we show how to implement the strategies of a quantum game through controlled adiabatic evolutions, where we ...
Dynamical phase transitions and Loschmidt echo in the infinite-range XY model
(Royal Soc, 2016)
We compare two different notions of dynamical phase transitions in closed quantum systems. The first is identified through the time-averaged value of the equilibrium-order parameter, whereas the second corresponds to ...
Factorization and criticality in the anisotropic XY chain via correlations
(Mdpi Ag, 2015-01-01)
In this review, we discuss the zero and finite temperature behavior of various bipartite quantum and total correlation measures, the skew information-based quantum coherence and the local quantum uncertainty in the thermal ...
Phase transitions and thermodynamics of quasione- dimensional quantum rotor and spin systems
(Universidade Federal de Pernambuco, Fri )
Metric-Space Approach for Distinguishing Quantum Phase Transitions in Spin-Imbalanced Systems
Metric spaces are characterized by distances between pairs of elements. Systems that are physically similar are expected to present smaller distances (between their densities, wave functions, and potentials) than systems ...
Negative thermal expansion near two structural quantum phase transitions Connor
Recent experimental work has revealed that the unusually strong, isotropic structural negative thermal expansion in cubic perovskite ionic insulator ScF3 occurs in excited states above a ground state tuned very near a ...