2013/09/30 by Robert Jirschik, Michael J. Hartmann
Computer Science · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Decoupling (probability) #Dissipative system #Excitation #Interferometry #Josephson effect #Optics #Photon #Physics #Quantum #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum electrodynamics #Quantum mechanics #Quantum tunnelling #Qubit #Resonator #Superconductivity #cond-mat.mes-hall #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.1140/epjqt4
published as EPJ Quantum Technology 1, 4 (2014) · revised, comparison of numerics and mean-field added
arxiv created 2013/11/29 · openalex publication_date 2014/01/29 · arxiv updated 2014/03/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Arrays of circuit cavities offer fascinating perspectives for exploring quantum many-body systems in a driven dissipative regime where excitation losses are continuously compensated by coherent input drives. Here we investigate a system consisting of three transmission line resonators, where the two outer ones are driven by coherent input sources and the central resonator interacts with a superconducting qubit. Whereas a low excitation number regime of such a device has been considered previously with a numerical integration, we here specifically address the high excitation density regime. We present analytical approximations to these regimes in the form of two methods. The first method is a Bogoliubov or linear expansion in quantum fluctuations which can be understood as an approximation for weak nonlinearities. As the second method we introduce a combination of mean-field decoupling for the photon tunneling with an exact approach to a driven Kerr nonlinearity which can be understood as an approximation for low tunneling rates. In contrast to the low excitation regime we find that for high excitation numbers the anti-bunching of output photons from the central cavity does not monotonously disappear as the tunnel coupling between the resonators is increased.