量子ロジックによる単一の電子スピンの繰り返し読み出し,核スピンの従属である量子ロジックによる反復読み出し

L Jiang¹, J S Hodges, J R Maze

¹Department of Physics, Harvard University, Cambridge, MA 02138, USA.

Science (New York, N.Y.)

|September 12, 2009

まとめ

研究者らは,核スピンアニキレイを使用して単一の電子スピンクビット読み取りを強化しました. この10倍信号の改善は,量子コンピューティングとセンシングアプリケーションにとって極めて重要です.

科学分野:

量子情報科学とは,量子情報科学である.
固体物理固体物理学

背景:

単一の量子ビット (量子ビット) の堅牢な測定は,量子計算,通信,計測,およびセンシングに不可欠です.
固体系の電子スピン量子ビットの現在の読み取り方法は,感度と速度に制限があります.

研究の目的:

単一の電子スピン量子ビットの読み取りのための改良された方法を実装する.
信号振幅と量子ビット状態測定の精度を高めるために.
堅牢な量子情報プロセッサの開発を進めること.

主な方法:

単一の電子スピンと近接核スピンのシステム上の量子論理操作を活用した.
室温ダイアモンドの単一の窒素空白 (NV) センターの一貫した操作を採用しました.
単一の核スピンメモリと,核スピンアシラエの2段階の連結された手順を実装しました.

主要な成果:

電子核スピンシステムの完全な量子制御 (最大3回) を達成しました.
単一の核スピンメモリを使用して,電子スピン読み出しの信号振幅を10倍増幅することが実証されました.
読み取りをさらに改善するために,一対の核スピンアンキリアを用いた連結された手順を提示しました.

結論:

開発された技術は,単一の電子スピン量子ビットの読み取りを大幅に改善します.
この方法は,電子と核のスピンを利用した堅牢な量子情報プロセッサの実現に不可欠です.
この技術は,スピンベースのナノスケールのダイヤモンド磁気計の感度と速度を向上させる可能性を秘めています.

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