共振交換量子ビットを使ったコヘランス・スピン・フォトン・カップリング
A J Landig1, J V Koski2, P Scarlino2
1Department of Physics, ETH Zürich, Zurich, Switzerland. alandig@phys.ethz.ch.
Nature
|July 27, 2018
まとめ
研究者は単一のマイクロ波光子と 3電子スピン量子ビットとの強い結合を達成しました この画期的な発見は,量子計算のためのスピン量子ビットの 協調的な長距離結合を可能にすることで,量子情報処理を進めている.
科学分野:
- 量子情報科学
- 固体物理学
- 量子コンピューティング
背景:
- 電子のスピンは長いコヒーレンス時間のために量子計算に有望である.
- 距離のスピンのコヒーレントカップリングはスケーラブルな量子情報処理に不可欠です
- フォトンは量子情報伝達器として機能し 遠隔スピン相互作用を可能にします
研究 の 目的:
- 単一のマイクロ波光子と3電子のスピンクビットとの強い結合を証明する.
- 量子ビット-光子結合の強さと量子ビットの脱合率を調査する.
- 量子ビットの電気二極モメントへの依存を 探求する
主な方法:
- ナイオビウム・タイタニウム・ナトリド高阻力共振器と 3つの量子ドットを持つガリウム・アルセニド装置を用いて
- 強い結合の証拠として,真空ラビモードの分裂を観察する.
- 量子ビット-光子結合の強さの依存度を測定するために AC スターク効果を使用します.
主要な成果:
- 単一のマイクロ波光子と3電子スピン量子ビットとの強い結合を達成しました.
- 約31MHzのコヒーレントカップリング強度と約20MHzの量子ビットの脱コヒーレンス率を観測した.
- ~23MHzのカップリング強度で,最低速度の~10MHzまでデコヘレンスの静電チューニングが実証されています.
結論:
- 強力な量子ビット-光子カップリングの実証は,一貫した長距離スピン量子ビットカップリングの重要な進歩です.
- この研究は,スケーラブルな量子ネットワークと,スピン量子ビットを用いた分散量子コンピューティングの道を開きます.
- 量子システムに 精密な制御を 提供します
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