Study of quantum correlations of qubits in remote cavities: biphotonic vs uniphotonic processes in each cavity
Abstract
The aim of this work is to study the quantum correlations, entanglement and discord, of two qubits, each one located in its respective cavity, which interact with a common reservoir. Each qubit interacts with its own respective cavity through the emission/absorption of two correlated photons (bi-photon). Initially, the atoms are considered in a type of Bell-diagonal state and the cavities in the empty state. The evolution of the correlations is calculated and, for the model with biphotonic interactions without losses of photons through the cavity, the freezing effect of the correlations is found. When there are uniphotonic or biphotonic losses toward the reservoir, a decay of the correlations is evidenced. It is observed that qubits are entanglement over a longer period of time when biphotonic interactions and losses are considered.
Keywords
Quantum correlations, Bi-photon, Qubit, Entanglement, Quantum discord
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