Transition-Edge Sensors (TESs) are extremely sensitive microcalorimeters, which take advantage of the sharpness of the superconducting transition. Use of proximity Mo/Au bilayers allows tuning critical temperature Tc. Study of superconducting proximity effect reveals a high quality interface and tracks the evolution of Tc with layers thicknesses. Nevertheless, the transition is hugely broadened by current, which can be interpreted as current-driven vortex-antivortex depairing. Both effects have impact on performances of TES-based radiation detectors, in development at the ICMAB.

Large current-induced broadening of the superconducting transition in Mo/Au transition edge sensors
Lourdes Fabrega, Agustin Camon, Carlos Pobes, Pavel Strichovanec, Raquel Gonzalez-Arrabal
Superconductor Science and Technology 32, 1, 015006, 2019
DOI: 10.1088/1361-6668/aaebf4

Figure: Cross-section TEM image of a Mo/Au bilayer deposited on a Si3N4 membrane; room temperature growth is required to prevent strains in the Mo layer and Si3N4 membrane. Columnar morphology is appreciated, as well as a flat, sharp Mo/Au interface, which results in very narrow superconducting transitions.

Coordination
Anna May-Masnou This email address is being protected from spambots. You need JavaScript enabled to view it.
Redaction
Anna May-Masnou This email address is being protected from spambots. You need JavaScript enabled to view it.
Web & Graphic Editor
José Antonio Gómez  This email address is being protected from spambots. You need JavaScript enabled to view it.

Webmasters
José Antonio Gómez This email address is being protected from spambots. You need JavaScript enabled to view it.
Albert Moreno     This email address is being protected from spambots. You need JavaScript enabled to view it.
ICMAB