Speaker
Description
The direct current Superconductive Quantum Interference Device (dc SQUID) is one of the most established applications of superconductor technology. Their often-unrivalled sensitivity to magnetic flux translates into numerous applications for SQUID sensors, such as low-temperature thermometry or current sensing for electrical metrology.
In this contribution, we present the integration of superconductive, sub-micrometric Nb “fine-pitch” coils into existing Nb/AlOx/Nb SQUID designs for improved signal input. The “fine-pitch” coil layouts allow to significantly extend the range of input inductances and increased signal-to-SQUID inductive coupling while maintaining the SQUID loop inductance and the overall compactness of the sensors. In a SQUID current sensor, to maximize the inductive coupling constant k between the signal input coil and the SQUID loop, means to achieve a low coupled energy sensitivity ε$_{c}$ = (1/k$^{2}$)$\times$ ε - where ε is the SQUID-intrinsic energy sensitivity.
The contribution will provide details of the fabrication process and design aspects of the integrated sensors, as well as characterization results.
