グラフェンベースのジョセフソン交差点マイクロ波ボロメーター
Gil-Ho Lee1,2, Dmitri K Efetov3, Woochan Jung2
1Department of Physics, Harvard University, Cambridge, MA, USA.
Nature
|October 1, 2020
まとめ
超薄型グラフェンボロメーターを開発しました 非常に敏感なマイクロ波検出器です この新しいセンサーは 熱力学的な限界を達成し ラジオ天文学と量子科学の応用を 進めるのです
科学分野:
- 物理学
- 材料科学
- 量子技術
背景:
- 繊細なマイクロ波探知器は 放射性天文学や ダークマターのアクシオン探索や 量子情報科学に不可欠です
- 従来のボロメーターは,表面と体積の比率が大きいため,光子結合と材料の安定性に関する制限に直面しています.
- ボロメーターの感受性を高めるための典型的なアプローチは,より小さなデバイスのナノ製造です.
研究 の 目的:
- 単層グラフェンを基にした超薄ボロメトリックセンサーを提示します.
- 従来のボロメーターの限界を克服し グラフェンの独特の熱と電子特性を利用する
- マイクロ波の検出で前代未聞の 感度を達成するために
主な方法:
- 超伝導体-グラフェン-超伝導体ジョセフソン結合ボロメーターを開発した.
- 7.9GHzの共振周波数と99%以上の結合効率を持つマイクロ波共振器にジョセフソン接続を埋め込みました.
- グラフェンの低電子特異熱と熱伝導性を利用した.
主要な成果:
- 7 × 10−19 W/√Hzのノイズ等価の電力を達成した.
- 単一の32GHz光子に相当するエネルギー解像度を示した.
- 0.19Kでの熱変動による基本的感受性限界に達した.
結論:
- 単層グラフェンは超敏感なボロメトリックセンサーの開発を可能にします.
- 超伝導体-グラフェン-超伝導体ジョセフソン結合ボロメーターは,検出器技術の重要な進歩を表しています.
- 熱力学的な限界のボロメーターを 作るには 二次元材料が有望です
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