A distributed, active patch antenna model of a Josephson oscillator

Abstract

Optimization of Josephson oscillators requires a quantitative understanding of their microwave properties. A Josephson junction has a geometry similar to a microstrip patch antenna. However, it is biased by a dc-current, distributed over the whole area of the junction. The oscillating electric field is generated internally via the ac-Josephson effect. In this work I present a distributed, active patch antenna model of a Josephson oscillator. It takes into account the internal Josephson electrodynamics and allows determination of the effective input resistance, which couples Josephson current to cavity modes in the transmission line formed by the junction. The model provides full characterization of Josephson oscillators and explains the origin of low radiative power efficiency. Finally, I discuss the design of an optimized Josephson patch oscillator, capable of reaching high efficiency and radiation power for emission into free space.

12 pages, 4 Figs, 2 Tables

References in corpus (5)

• Hot spots and waves in Bi2Sr2CaCu2O8 intrinsic Josephson junction stacks -a study by Low Temperature Scanning Laser Microscopy
• THz emission from a stacked coherent flux-flow oscillator: non-local radiative boundary conditions and the role of geometrical resonances
• Observation of superluminal geometrical resonances in Bi2Sr2CaCu2O8+x intrinsic Josephson junctions
• Direct visualization of phase-locking of large Josephson junction arrays by surface electromagnetic waves
• Design aspects of Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta }$ THz sources: optimization of thermal and radiative properties

Cited by in corpus (4)

• Terahertz emission from mutually synchronized standalone Bi2Sr2CaCu2O8+x intrinsic-Josephson-junction stacks
• Resonant switching current detector based on underdamped Josephson junctions
• Cascade switching current detectors based on arrays of Josephson junctions
• Planar Josephson junctions for sensors and electronics:Different geometry, new functionality