製造されたスピンで量子アニリングを行う

M W Johnson¹, M H S Amin, S Gildert

¹D-Wave Systems Inc., 100-4401 Still Creek Drive, Burnaby, British Columbia V5C 6G9, Canada. mwjohnson@dwavesys.com

Nature

|May 13, 2011

まとめ

研究者は,基底状態を見つけるために人工スピンシステムで量子アニリングを実演しています. このプログラム可能なシステムは,複雑な最適化問題を解決するための新しいアプローチを提供します.

科学分野:

量子コンピューティング
凝縮物質物理学凝縮物質物理学
計算科学計算科学とは

背景:

相互作用するスピンシステムの基本状態を特定することは,計算上非常に難しいことです.
量子アニリングは,このような問題を解決するための有望な方法ですが,物理的な実装は限られています.
現在の研究は主に凝縮物質系における顕微鏡のスピンに焦点を当てている.

研究の目的:

人工イシングスピンシステムの基本状態を見つけるために量子アニリングを使用する.
スピンシステムを研究するためのプログラム可能な人工スピンネットワークを実証する.
理論的モデルとスピンネットワークの実験的調査の間のギャップを埋めるために.

主な方法:

8個の超伝導フルス量子ビットの配列に量子リニールを採用した.
多様なスピンネットワークを作成するために,設定可能なプログラム可能なスピン-スピンカップリングを構成します.
低エネルギー構成への移行を観察するために,システムのダイナミクスを監視します.

主要な成果:

人工イシングスピンシステムの基本状態を成功裏に発見しました.
量子アニリングの独特な特徴を観察し,古典的な熱アニリングと区別しました.
様々なスピンネットワークのトポロジーのためにシステムの再構成を in situ で再構成する能力を実証しました.

結論:

プログラム可能な人工スピンネットワークは,量子解熱のための実用的な物理システムとして機能します.
このアプローチは,難しい組み合わせ最適化問題のより効果的な解決策につながる可能性があります.
このシステムのスケーリングは,実用的な量子アルゴリズムの実装を可能にします.

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