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Updated: Feb 22, 2026

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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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ジョセフソン効果による一貫したマイクロ波の生成
Angelo Greco1, Xavier Ballu2, Francesco Giazotto2
1NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, Pisa, Italy. angelo.greco@nano.cnr.it.
Nature communications
|February 20, 2026
まとめ
研究者らは,超伝導回路を用いた新しいマイクロ波周波数コンブジェネレーターを実証した. このオンチップデバイスは,ACジョセフソン効果を活用して,正確なギガヘルツからテラヘルツの周波数を生成し,量子技術の道を開く.
科学分野:
- 固体物理学 固体物理学とは
- 量子光学とは,量子光学である.
- マイクロウェーブ技術とは
背景:
- 光学周波数は,正確な測定ツールです.
- 超伝導回路は,周波数を生成するための低分散プラットフォームを提供します.
- 先進的なアプリケーションでは,周波数のオンチップ統合が望ましい.
研究 の 目的:
- 超伝導回路を使用して一貫したマイクロ波周波数を生成することを実証する.
- オンチップコンブエミターにおけるACジョセフソン効果の可能性を調査する.
- 超伝導周波数の性能とスケーラビリティを評価する.
主な方法:
- 超伝導量子干渉装置 (SQUID) を利用した.
- 周期的な電圧パルスを生成するために,時間依存の磁気ドライブを適用しました.
- 周波数領域で生成された電圧パルスを分析して,の性質を特徴づけました.
主要な成果:
- 数十のスペクトルモード (モード46まで) を含む一貫したマイクロ波周波数カム生成を達成しました.
- 観測された放出力は,各ハーモニクあたり -170 dBm から -130 dBm までであった.
- 4-8GHz帯域幅内で40dBのダイナミックレンジを示した.
- マイクロメートルスケールの装置を最小限の消耗で製造しました.
結論:
- 超伝導回路は,チップ内マイクロ波周波数の生成のための実行可能なプラットフォームを提供します.
- ACジョセフソン効果は,これらのを作るための重要なメカニズムです.
- 開発された技術は,冷凍電子技術や量子技術との統合に有望である.
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