In order to realize efficient coupling between Flux-Flow type Josephson Oscillator (FFO) and an external stripline, we have carried out experiments to investigate the inductive coupling scheme in strong coupling regime. By adopting NbN films with large penetration depths as electrodes for strong coupling, we have realized coupling sections with coupling coefficient a M/L1L2 as large as 0.7, with M, Ll and L2 being mutual inductance, self inductances of FFO and the stripline, respectively. Employing this design for the coupling, we have succeeded in detecting ac fields at frequencies around 150 GHz, which were emitted from FFO to the stripline via the coupling section. The present results suggest the excellence of the strong coupling regime in inductive coupling scheme with respects to output power as well as bandwidth.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering