On-chip microwave coherent source with in-situ control of the photon number distribution

Year: 2025

Authors: Mastrovito P., Ahmad HG., Porzio A., Esposito M., Massarotti D., Tafuri F.

Autors Affiliation: Univ Napoli Federico II, Dipartimento Fis Ettore Pancini, Naples, Italy; Univ Napoli Federico II, Dipartimento Ingn Elettr & Tecnol Informaz, via Claudio, Naples, Italy; CNR SPIN Complesso di Monte S Angelo, Naples, Italy; Univ Cassino & Lazio Meridionale, Dipartimento Ingn Civile & Meccan DICEM, Cassino, Italy; CNR Ist Nazl Ott CNR INO, Largo Enr Fermi 6, Florence, Italy.

Abstract: Coherent photon sources are key elements in different applications, ranging from quantum sensing to quantum computing. The possibility of designing and engineering superconducting circuits behaving like artificial atoms supports the realization of quantum optics protocols, including microwave photons generation. Here we propose and theoretically investigate a design that allows a tunable photon injection directly on-chip. Our approach enables control of the emission via an external knob while preserving, in principle, the stability and linewidth characteristics. This is achieved by replacing the conventional capacitive link between the source and the reservoir with a tunable coupler, with the advantage of avoiding direct dynamical manipulation of the photon source dynamics, providing pulsed control of the emission. We validate the dynamical control of the generated state under the effect of an external flux threading the tunable coupler and discuss the possibility of employing this scheme also in the context of multiple bosonic reservoirs.

Journal/Review: COMMUNICATIONS PHYSICS

Volume: 8 (1)      Pages from: 295-1  to: 295-12

More Information: The authors thank F. Nori for the fruitful discussion and would also like to thank G. Di Bello and M. Vizzuso for their help in the work development. The work was supported by the Pathfinder EIC 2023 project FERROMON-Ferrotransmons and Ferrogatemons for Scalable Superconducting Quantum Computers, by the project Superconducting quantum-classical linked computing systems (SuperLink), in the frame of QuantERA2 ERANET COFUND in Quantum Technologies, and by the Project PRIN 2022-Advanced Control and Readout of scalable Superconducting NISQ Architectures (SuperNISQ)-CUP E53D23001910006. The research activities were also supported by the PNRR MUR project PE0000023-NQSTI and the PNRR MUR project CN_00000013-ICSC.
KeyWords: Quantum Error-correction; Single-photon; States; Laser; Noise; Limit
DOI: 10.1038/s42005-025-02219-6