Protecting quantum resources via frequency modulation of qubits in leaky cavities

TL;DR

This paper demonstrates that frequency modulation of qubits in leaky cavities can significantly extend quantum resource lifetimes, offering a practical approach to mitigate decoherence in quantum systems.

Contribution

It introduces a frequency modulation technique to enhance quantum resource preservation in open systems, with detailed analysis and scalability considerations.

Findings

Achieved four orders of magnitude increase in coherence lifetime for a single qubit.

Extended entanglement, discord, and coherence lifetimes by three orders of magnitude.

Feasibility discussed within circuit-QED systems for practical implementation.

Abstract

Finding strategies to preserve quantum resources in open systems is nowadays a main requirement for reliable quantum-enhanced technologies. We address this issue by considering structured cavities embedding qubits driven by a control technique known as frequency modulation. We first study a single qubit in a lossy cavity to determine optimal modulation parameters and qubit-cavity coupling regime allowing a gain of four orders of magnitude concerning coherence lifetimes. We relate this behavior to the inhibition of the qubit effective decay rate rather than to stronger memory effects (non-Markovianity) of the system. We then exploit these findings in a system of noninteracting qubits embedded in separated cavities to gain basic information about scalability of the procedure. We show that the determined modulation parameters enable lifetimes of quantum resources, such as entanglement, discord and coherence, three orders of magnitude longer than their natural (uncontrolled) decay times. We discuss the feasibility of the system within the circuit-QED scenario, typically employed in the current quantum computer prototypes. These results provide new insights towards efficient experimental strategies against decoherence.