シリコン量子プロセッサーユニット・セル1ケルビン以上の動作

C H Yang¹, R C C Leon², J C C Hwang^2,3

¹Centre for Quantum Computation and Communication Technology, School of Electrical Engineering and Telecommunications, University of New South Wales, Sydney, New South Wales, Australia. henry.yang@unsw.edu.au.

Nature

|April 17, 2020

まとめ

研究者は2つの量子ビットを持つスケーラブルなシリコン量子プロセッサユニットセルを開発しました. この突破により量子コンピュータはより高い温度で動作しよりシンプルな冷却システムを使うことができます

科学分野:

量子コンピューティング
固体物理学
材料科学

背景:

量子コンピュータのスケーリングは,熱生成と冷却能力によって制限されます.
現在の固体量子ビット技術は,大規模な量子ビット数を達成する上で大きな課題に直面しています.

研究の目的:

高温で動作するスケーラブルなシリコン量子プロセッサユニット・セルを実証する.
集積された古典的な制御エレクトロニクスを持つ量子コンピュータの開発を可能にします.

主な方法:

シリコン量子プロセッサーユニットセルを 2つの量子ビットで量子ドットに閉じ込めました
電子トンネリングによる初期化と読み取りのための電子貯蔵庫から分離された量子ドット.
同位体濃縮のシリコンでコヒーレントクビット制御のための電気駆動スピン共振を使用.

主要な成果:

単一量子ビットのゲートの精度が98.6%で,コヒーレンス時間は1.5ケルビンで2マイクロ秒です.
低磁場 (0.1テスラ) で量子ビットのエネルギーが熱エネルギー以下で動作が証明されている.
エラー修正アーキテクチャと互換性のあるユニットセルを展示し,何百万もの量子ビットにスケーラブルにしました.

結論:

このシリコン量子プロセッサユニットは拡張可能な量子コンピュータの基本的な構成要素です
1.5 ケルビンでの操作は可能であり,より単純なポンプ式4He冷却システムの使用の可能性を示唆しています.
この進歩により古典的な制御エレクトロニクスと量子ビット配列の統合が可能になりスケーリング上の大きな障害を克服できます

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