Decoherence of two qubits coupled with one-mode cavity without rotating-wave approximation

TL;DR

This paper investigates the exact decoherence dynamics of two qubits coupled to a single-mode cavity without using the rotating-wave approximation, revealing non-Markovian effects and entanglement revival phenomena.

Contribution

It provides an exact analysis of two-qubit decoherence beyond the Jaynes-Cummings model, highlighting differences in entanglement behavior under strong coupling and detuning.

Findings

Decoherence is similar to Markovian at weak coupling in resonant case.

Entanglement can vanish and recover multiple times under strong coupling.

Periodic entanglement revival occurs in detuning case.

Abstract

The decoherence of two qubits, coupled with one-mode cavity separately, has been investigated exactly. The results show that, for the resonant case, the decoherence behavior of system is similar to Markovian case when the coupling strength is weak, while the concurrence vanishes in finite time and might recover fractional initial entanglement before it permanently vanishes when the coupling strength is strong. And for detuning case, the entanglement could periodically recover after a period of time from its disappearance. These results are quite different from that of system subjected to Jaynes-Cummings model.