Radiation amplification with help of the intrinsic Josephson effect

A. I. Larkin, Yu. N. Ovchinnikov

Grzegorz Jung, Janusz Konopka, Stefano Vitale

P. T. Parrish

Ch. Preis, Manas Sardar, J. Keller

The use of the intrinsic Josephson effect in layered high-Tc superconductors for parametric amplification of a signal in the presence of a strong pump radiation is investigated. Model calculations are performed both for thin films and massive material with a surface parallel to the c direction assuming normal incidence of the radiation with electric field parallel in c direction. In both cases a positive signal gain is obtained in a limited range of frequencies and pump power.

D. E. McCumber

Lev N. Bulaevskii, Alexei E. Koshelev, M. Tachiki

Single crystals of layered high-temperature superconductors intrinsically behave as stacks of Josephson junctions. We analyze response of current-biased stack of intrinsic junctions to irradiation by the external electromagnetic (em) wave. In addition to well-known Shapiro steps in the current-voltage characteristics, irradiation promotes stimulated radiation which adds with spontaneous Josephson radiation from the crystal. Such enhancement of radiation from current-biased crystal may be used for amplification of em waves. Irradiation also facilitates synchronization of Josephson oscillations in all intrinsic Josephson junctions of a single crystal as well as oscillations in intrinsic junctions of different crystals.