Shielding quantum discord through continuous dynamical decoupling

Abstract

This work investigates the use of dynamical decoupling to shield quantum discord from errors introduced by the environment. Specifically, a two-qubits system interacting with independent baths of bosons is considered. The initial conditions of the system were chosen as pure and mixed states, while the dynamical decoupling has been achieved by means of continuous fields. The effects of the temperature on the shielding of quantum discord is also studied. It is shown that although the quantum discord for particular initial states may be perfectly preserved over some finite time window in the absence of any protective field, the effectiveness of the dynamical decoupling with continuous fields depends essentially on the timescale required to preserve quantum discord. It is also shown that for these particular initial states the time for which the shielding of the quantum discord becomes effective decreases as the temperature increases.

7 pages, 7 figures

References in corpus (10)

• Device-independent security of quantum cryptography against collective attacks
• Classical and quantum correlations under decoherence
• Interpreting quantum discord through quantum state merging
• Operational interpretations of quantum discord
• Linking Quantum Discord to Entanglement in a Measurement
• Quantum discord bounds the amount of distributed entanglement
• Conservation law for distributed entanglement of formation and quantum discord
• Quantum cost for sending entanglement
• Entanglement irreversibility from quantum discord and quantum deficit
• Alternative fidelity measure for quantum states