title: Deterministic Down-Converter and Continuous Photon-Pair Source within the Bad-Cavity Limit.
abstract: The development, characterization, and control of N-photon sources are instrumental for quantum technological applications. This work constitutes a step forward in this direction, where we propose a cavity quantum electrodynamics setup designed for the generation of photon pairs. We identify both the regime where our system works as a deterministic down-converter of a single input photon and as an optimal two-photon source under weak continuous driving. We use both the scattering and master equation formalisms to characterize the system, and from their connection naturally arises a physical criterion characterizing when weakly driven systems behave as continuous antibunched two-photon sources. We also show that the outgoing photons share nontrivial quantum correlations in general. We provide a specific implementation based on state-of-the-art superconducting circuits, showing how our proposal is within the reach of current technologies. As an outlook, we show the proposal can be extended to achieve deterministic conversion of a single photon into N photons.
authors.affiliation: Max-Planck Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany.
authors.forename: Yue
authors.initials: Y
authors.lastname: Chang
authors.affiliation: Max-Planck Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany.
authors.forename: Alejandro
authors.initials: A
authors.lastname: González-Tudela
authors.affiliation: Max-Planck Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany.|Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Sánchez Muñoz
authors.affiliation: Max-Planck Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany.|Institute for Theoretical Physics II, Universität Erlangen-Nürnberg, Staudtstrasse 7, 91058 Erlangen, Germany.
authors.forename: Carlos
authors.initials: C
authors.lastname: Navarrete-Benlloch
authors.affiliation: Max-Planck Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany.
authors.forename: Tao
authors.initials: T
authors.lastname: Shi