Simulation and measurement of millimeter-wave radiation from Josephson junction array**Project supported by the National Natural Science Foundation of China (Grant No. 51002081), the Fundamental Research Funds for the Central Universities, China, the China Manned Space Advance Research Program, China (Grant No. 030201), and the Research Program of Application Foundation and Advanced Technology of Tianjin, China (Grant No. 15JCQNJC01300).

Abstract

We report the circuit simulations and experiments of millimeter-wave radiation from a high temperature superconducting (HTS) bicrystal Josephson junction (BJJ) array. To study the effects of junction characteristic parameters on radiation properties, new radiation circuit models are proposed in this paper. The series resistively and capacitively shunted junction (RCSJ) models are packaged into a Josephson junction array (JJA) model in the simulation. The current-voltage characteristics (IVCs) curve and radiation peaks are simulated and analyzed by circuit models, which are also observed from the experiment at liquid nitrogen temperature. The experimental radiation linewidth and power are in good agreement with simulated results. The presented circuit models clearly demonstrate that the inconsistency of the JJA will cause a broad linewidth and a low detected power. The junction radiation properties are also investigated at the optimal situation by circuit simulation. The results further confirm that the consistent JJA characteristic parameters can successfully narrow the radiation linewidth and increase the power of junction radiation.