量子エレクトロニクス. 単回転量子ビットで通常の金属でジョンソンノイズと弾道輸送を検知する
S Kolkowitz1, A Safira1, A A High2
1Department of Physics, Harvard University, Cambridge, MA 02138, USA.
まとめ
研究者はダイヤモンドの窒素空白 (NV) センターを使用して,銀のフィルムにジョンソンノイズを測定しました. 彼らは,ナノスケールでオームの法則から逸脱する単結晶フィルムの抑制されたノイズを観察しました.
科学分野:
- 凝縮物質物理学 凝縮物質物理学
- 量子センシングとは,量子センシングです.
- ナノテクノロジー ナノテクノロジー
背景:
- ジョンソンノイズは,導体内の熱誘導電流から生じる.
- これらの変動は,金属の伝導性に関連した電気および磁場を生成します.
- ナノスケールの電磁環境の探査は,量子技術にとって極めて重要です.
研究 の 目的:
- シングルスピン量子ビットを用いて,導電性シルバーフィルムの近くのジョンソンノイズを調査する.
- ナノスケールでの古典的電磁理論からの偏差を探求する.
- ジョンソンノイズに対する材料構造 (多結晶対単結晶) の影響を理解する.
主な方法:
- 繊細な磁気計としてダイヤモンドの窒素空白 (NV) センターを活用した.
- 銀のフィルム付近で測定された磁気変動 (ジョンソンノイズ).
- 多結晶フィルムと単結晶フィルムの異なる距離 (20~200 nm) と温度 (10~300 K) を設定する.
主要な成果:
- クラシックなジョンソンノイズ行動は,ポリクリスタリンシルバーフィルムで観察されました.
- 単結晶シルバーフィルムの近くで,ジョンソンノイズの有意な抑制が検出されました.
- この抑制は,電子の自由経路の平均値を下回る長さスケールでのオムの法則からの偏差を示します.
結論:
- 結果は,弾道的な電子運動を組み込んだ一般的なモデルと一致しています.
- 近隣の電極でナノスケールの量子システムを制御する可能性を実証した.
- ナノスケールの電磁現象における物質構造の重要性を強調する.
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