The effect of bias feed profile on spectral properties of noisy Josephson flux flow oscillator

TL;DR

This study investigates how different bias current profiles affect the spectral linewidth of a Josephson flux flow oscillator, aiming to optimize a noisy spectrometer in the subTHz range.

Contribution

It provides new insights into how bias profiles influence spectral properties, comparing overlap and inline junction geometries for improved oscillator design.

Findings

Spectral linewidth can be increased threefold with moderate power reduction.

Bias current profile significantly impacts the spectral linewidth.

Inline junction geometry shows distinct spectral behavior.

Abstract

For creation of a noisy non-stationary spectrometer working in the subTHz frequency range the power and spectral characteristics of a flux flow oscillator (FFO), based on a long Josephson junction are studied. The effect of various bias current profiles on the spectral linewidth of long overlap Josephson junction are investigated and comparison with the inline junction geometry is outlined. It has been demonstrated that the spectral linewidth can be increased by a factor of three with the moderate reduction of emitted power.