Response and Amplification of Terahertz Electromagnetic Waves in Intrinsic Josephson Junctions of Layered High-Tc Superconductor

摘要

We investigate the response of a stack of intrinsic Josephson junctions(IJJs) to terahertz (THz) electromagnetic (EM) irradiation. A significantamplification of the EM wave can be achieved by the IJJs stack when theincident frequency equals to one of the cavity frequencies. The irradiationexcites pi phase kinks in the junctions, which stimulate the cavity resonancewhen the bias voltage is tuned. A large amount of dc energy is then pumped intothe Josephson plasma oscillation, and the incident wave gets amplified. Fromthe profound current step in IV characteristics induced at the cavityresonance, the system can also be used for detection of the THz wave.