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arXiv · 2609.21473

Development of a Temperature-Variable Cold Blackbody Calibrator for Millimeter and Submillimeter Wave Detectors

Kazuki Watanabe·Taiki Sato·Shuhei Inoue·Shinsuke Uno·Tatsuya Takekoshi·Tai Oshima
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Abstract

We report the design, fabrication, and characterization of a cryogenic blackbody calibrator intended for laboratory-based detector characterization, providing multi-temperature calibration of millimeter- and submillimeter-wave detectors over a temperature range of 4 K to ~10 K. The device employs a Stycast/SiC absorber shaped for uniform array illumination and mounted on a phosphor-bronze substrate with optimized thermal links. Measured thermal conductance and heat capacity show the expected temperature dependence, although the conductance was lower than estimated, yielding a thermal time constant of 8.5 s at 10 K versus the 3.7 s design estimate. The response remains practical, demonstrating the calibrator's effectiveness as a stable reference source for precise calibration of detector arrays.

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Kazuki Watanabe, Taiki Sato, Shuhei Inoue, Shinsuke Uno, Tatsuya Takekoshi, Tai Oshima. 2026-09-18. Development of a Temperature-Variable Cold Blackbody Calibrator for Millimeter and Submillimeter Wave Detectors. https://doi.org/10.1109/tasc.2026.3722206

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