Decoherence suppression with both spontaneous emission and dephasing by non-Hermitian operation

Abstract

Decoherence suppression from disturbance of the environment is an essential task in quantum information processing. Using the non-Hermitian operation approach, decoherence suppression of a qubit system interacting with a zero-temperature reservoir with both spontaneous emission and dephasing is investigated. We derive the exact analytical expressions of the quantum fidelity and find that quantum coherence can be significantly enhanced by controlling the non-Hermitian operator parameters. In particular, the non-Hermitian is more effective in the case of strong decay rates and show better inhibition effect on dephasing process than the spontaneous emission process.