6533b825fe1ef96bd1282aa5

RESEARCH PRODUCT

Superradiant Quantum Phase Transition for an Exactly Solvable Two-Qubit Spin-Boson Model

Roberto GrimaudoAlessandro SergiAntonino MessinaDavide Valenti

subject

quantum phase transitionsSettore FIS/02 - Fisica Teorica Modelli E Metodi Matematicitwo-qubit spin-boson modelexactly solvable modelsGeneral Physics and Astronomyopen quantum systemsentanglementsuperradiance

description

A spin-boson-like model with two interacting qubits is analysed. The model turns out to be exactly solvable since it is characterized by the exchange symmetry between the two spins. The explicit expressions of eigenstates and eigenenergies make it possible to analytically unveil the occurrence of first-order quantum phase transitions. The latter are physically relevant since they are characterized by abrupt changes in the two-spin subsystem concurrence, in the net spin magnetization and in the mean photon number.

https://doi.org/10.3390/e25020187