Interaction of Electromagnetic Radiation with Josephson Microbridges in a Resonant Structure.

William H. Howard

Vladimir N. Gubankov, V. P. Koshelets, G. A. Ovsiannikov

Alexander N. Vystavkin, Vladimir N. Gubankov, V. P. Koshelets +1 more

S. Rombetto

É. M. Belenov, Сергей Иванович Веденеев, E. M. Golyamina

Indirect observations are reported of stimulated emission of electromagnetic radiation by superconducting Josephson tunnel junctions or microbridges in such junctions exhibiting the properties of a strip resonator. Excitation in the resonator of a field of frequency ω by Josephson radiation of frequency ωJ = 2ω gave rise to a current step in the current-voltage characteristics of Nb–oxide–Pb tunnel junctions and this step indicated that lasing occurred at the frequency ω.

N. F. Pedersen, O. H. Soerensen, J. Mygind +3 more

We report direct measurements of the Josephson radiation emitted in X band from a superconducting thin-film microbridge coupled to a resonance cavity. Power is emitted if one of the harmonics of the Josephson frequency is in the bandwidth of the receiver. The maximum power emitted during our experiment was 10−13 W. The Josephson radiation could easily be detected at frequencies off resonance.