Voltage Fluctuations in ac Biased Superconducting Transition-Edge Sensors

Abstract

We present a detailed analysis of the fundamental noise sources in superconducting transition-edge sensors (TESs), ac voltage biased at MHz frequencies and treated as superconducting weak links. We have studied the noise in the resistive transition as a function of bath temperature of several detectors with different normal resistances and geometries. We show that the excess noise, typically observed in the TES electrical bandwidth, can be explained by the equilibrium Johnson noise of the quasiparticles generated within the weak link. The fluctuations at the Josephson frequency and higher harmonics contribute significantly to the measured voltage noise at the detector bandwidth through the nonlinear response of the weak link with a sinusoidal current-phase relation.

arXiv comment9 pages, 7 figures

References in corpus (8)

• Longitudinal Proximity Effects in Superconducting Transition-Edge Sensors
• Complex impedance, responsivity and noise of transition-edge sensors: analytical solutions for two- and three-block thermal models
• Josephson effects in an alternating current biased transition edge sensor
• High Aspect Ratio Transition Edge Sensors for X-ray Spectrometry
• Complex impedance of TESs under AC bias using FDM readout system
• Normal metal - superconductor decoupling as a source of thermal fluctuation noise in transition-edge sensors
• Divergence at low bias and down-mixing of the current noise in a diffusive superconductor-normal metal-superconductor junction
• Josephson linewidth in a resistively-shunted model with non-sinusoidal current-phase relation

Cited by in corpus (8)

• A Review of X-ray Microcalorimeters Based on Superconducting Transition Edge Sensors for Astrophysics and Particle Physics
• An optical transition-edge sensor with high energy resolution
• Transition-Edge Sensors for cryogenic X-ray imaging spectrometers
• Mitigation of the Magnetic Field Susceptibility of Transition Edge Sensors using a Superconducting Groundplane
• Impact of the absorber coupling design for Transition Edge Sensor X-ray Calorimeters
• Slow electron-phonon relaxation controls the dynamics of the superconducting resistive transition
• Demonstration of Weak-Link Physics in the Dynamical Response of Transition-Edge Sensors
• Fluctuation-driven excess noise near superconducting phase transition