Improved photon blockade in the two-photon Jaynes–Cummings model by additional quantum interference

Abstract: In a two-photon Jaynes–Cummings model which consists of an atom interacting with a cavity mode with a two-photon interaction, we find the photon blockade effect can be largely improved by inducing a interference pathway. The interference pathway can be either a two-photon transition or an atom transition. The purity of the single photon can be improved by 10∼100 times, and we find the high purity of single photon is induced by combination of conventional and unconventional photon blockade. The method provides a way to improve the purity of single photon. Graphic Abstract: In a system consisting of a cavity coupled to a two-level atom via a two-photon interaction, the two photon state can be reduced by destructive interference between different transition pathways. © The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature 2024.