Single-Photon Detection with a Josephson Junction Coupled to a Resonator
Dmitry S. Golubev, E. Il’ichev, L. S. Kuzmin
Abstract
We use a semiclassical formalism to optimize a microwave single-photon detector based on switching events of a current-biased Josephson junction coupled to a resonator. To detect very rare events, the average time between dark counts ${\ensuremath{\tau}}_{\mathrm{dark}}$ should be maximized taking into account that the switching time ${\ensuremath{\tau}}_{\mathrm{sw}}$ should be sufficiently small. We demonstrate that these times can be tuned in a wide range by changing the junction parameters, and ${\ensuremath{\tau}}_{\mathrm{dark}}/{\ensuremath{\tau}}_{\mathrm{sw}}\ensuremath{\sim}{10}^{9}$ can be achieved. Therefore, a junction-resonator arrangement can be used to detect extremely low photon fluxes (e.g., for searching for galactic axions).