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arXiv · 2111.04632

The Simulation and Design of an On-Chip Superconducting Millimetre Filter-Bank Spectrometer

Gethin Robson·Adam J. Anderson·Peter S. Barry·Simon Doyle·Kirit S. Karkare
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Abstract

Superconducting on-chip filter-banks provide a scalable, space saving solution to create imaging spectrometers at millimetre and sub-millimetre wavelengths. We present an easy to realise, lithographed superconducting filter design with a high tolerance to fabrication error. Using a capacitively coupled $\lambda/2$ microstrip resonator to define a narrow ($\lambda/\Delta\lambda = 300$) spectral pass band, the filtered output of a given spectrometer channel directly connects to a Lumped Element Kinetic Inductance Detector (LEKID). We show the tolerance analysis of our design, demonstrating $<11\%$ change in filter quality factor to any one realistic fabrication errors and a full filter-bank efficiency forecast to be 60\% after accounting for fabrication errors and dielectric loss tangent.

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Gethin Robson, Adam J. Anderson, Peter S. Barry, Simon Doyle, Kirit S. Karkare. 2021-11-08. The Simulation and Design of an On-Chip Superconducting Millimetre Filter-Bank Spectrometer. https://doi.org/10.1007/s10909-022-02747-3

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