電子を数えることに基づく容量基準
Keller1, Eichenberger, Martinis
1National Institute of Standards and Technology, Boulder, CO 80303, USA. National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
まとめ
新しい容量規格は,容量を正確に測定するために単電子トンネリングを使用しています. この量子ベースの方法は,高精度を達成し,容量測定のための自然な標準を提供します.
科学分野:
- メトロロジー・メトロロジー
- 量子エレクトロニクス 量子エレクトロニクス
- 電気工学 電気工学とは
背景:
- 正確な容量基準は,電気計量学にとって極めて重要です.
- 既存の規格は,基本的な物理定数との直接的なリンクが欠如している可能性があります.
- 量子現象は,高精度の新しい測定基準の可能性を秘めています.
研究 の 目的:
- 容量の定義に直接基づく容量規格を開発する.
- 精密な電荷移転のために単電子トンネリングを使用します.
- 容量に関する量子ベースの標準を確立する.
主な方法:
- 低温コンデンサを組み立てました.
- 既知の数の電子 (N) を基本的な電荷 (e) で転送するために,単一の電子トンネル装置を使用した.
- 結果の電圧変化 (ΔV) を測定し,電容量 (C = Ne/ΔV) を決定した.
主要な成果:
- 連続した電容量測定で 0.3 x 10−6 の相対標準偏差を達成しました.
- 基本的な電荷と電圧の測定に基づいて電容性を実現する方法を実証した.
- 開発された規格は,高い精度と再現性を示しています.
結論:
- シングル電子トンネリング法は,容量標準のための自然な基礎を提供します.
- この量子標準は,電圧のジョセフソン効果と抵抗の量子ホール効果に類似しています.
- この研究は,基本的な電容量標準を提供することによって,電気計量学の分野を前進させる.
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