2026-08-18 産業技術総合研究所
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＜関連情報＞
- https://www.aist.go.jp/aist_j/press_release/pr2026/pr20260818/pr20260818.html
- https://www.nature.com/articles/s41598-026-58868-2
交流および直流比測定の両方に対応する電流比較器（タイプa不確かさレベル10⁻⁸） Current comparator for both AC and DC ratio measurements with 10− 8-level type-a uncertainty
Hidekazu Muramatsu,Yuta Kainuma,Hiromitsu Kato,Norihiko Sakamoto,Tatsuji Yamada,Chiharu Urano,Hiroshi Abe,Shinobu Onoda,Takeshi Ohshima,Yuji Hatano,Mutsuko Hatano,Nobu-Hisa Kaneko,Yasutaka Amagai & Takayuki Iwasaki
Scientific Reports Published:11 August 2026
DOI:https://doi.org/10.1038/s41598-026-58868-2
Abstract
Accurate measurements of alternating current (AC) and direct current (DC) ratios are fundamental to electric power metrology. However, conventional current comparators for AC and DC typically rely on distinct technologies—electromagnetic induction for AC and superconducting quantum interference devices for DC. This technological divide leads to a fragmented and complex traceability system. Bridging this gap is critical for developing unified current standards that meet the demands of temperature power technologies. In this work, we present a compact, room-temperature AC/DC current comparator that integrates a diamond-based magnetometer using nitrogen-vacancy centers. The device achieves a type-A uncertainty at 10-8 level, while the expanded uncertainty is at 10-6 to 10-7 level, for both AC and DC signals and supports a system bandwidth up to 300HZ, without the need for cryogenics. It is comparable to the performance of typical AC comparators, and provides a compact and room-temperature operating platform for further performance improvement. This unified, cryogenics-free solution not only enhances precision and versatility but also expands the applicability of the system to DC resistance bridges in quantum electrical standards.
