Enhancing coherent energy transfer between quantum devices via a mediator

TL;DR

This paper explores how a quantum bus, especially a cavity with photons, can enhance energy transfer efficiency between quantum systems, potentially improving quantum device architectures.

Contribution

It demonstrates that cavity-mediated energy transfer becomes more efficient with more photons, unlike qubit-mediated transfer, offering new avenues for quantum technology design.

Findings

Cavity-mediated transfer efficiency increases with photon number.

Qubit-mediated transfer shows no advantage over direct coupling.

Quantum mediator speeds up energy transfer, enabling new architectures.

Abstract

We investigate the coherent energy transfer between two quantum systems mediated by a quantum bus. In particular, we consider the energy transfer process between two qubits, and how it can be influenced by using a third qubit or photons in a resonant cavity as mediators. Inspecting different figures of merit and considering both on and off-resonance configurations, we characterize the energy transfer performances. We show that, while the qubit-mediated transfer shows no advantages with respect to a direct coupling case, the cavity-mediated one is progressively more and more efficient as function of the number of photons stored in the cavity that acts as a quantum bus. The speeding-up of the energy transfer time, due to a quantum mediator paves the way for new architecture designs in quantum technologies and energy based quantum logics.