電子散乱によって初期化された結合された原子スピンシステムの自由相関的進化

Lukas M Veldman¹, Laëtitia Farinacci¹, Rasa Rejali¹

¹Department of Quantum Nanoscience, Kavli Institute of Nanoscience, Delft University of Technology, 2628 CJ Delft, the Netherlands.

Science (New York, N.Y.)

|May 28, 2021

まとめ

研究者はスキャニングトンネル顕微鏡を用いて結合された原子スピンを追跡しましたスピンが絡み合って角運動を交換するのはラーモアの周波数が一致する時だけだと観測し量子状態の移動の洞察を提供しています

科学分野:

量子力学
凝縮物質物理学
材料科学

背景:

結合量子システムのリアルタイムダイナミクスを理解することは量子状態の制御に不可欠です
局所刺激とその拡散は,多体量子システムにおける重要な現象である.

研究の目的:

結合した原子のスピンのリアルタイムの進化を調査する
クープリングされたスピンの間の絡み合いと角運動量交換の条件を調査する.
スキャントンネル顕微鏡を用いてスピンダイナミクスを探査する新しい方法を実証する.

主な方法:

スキャントンネル顕微鏡 (STM) を利用して,結合された原子スピンを探査した.
直流 (DC) ポンプ・プローブ・スキームを使用して,電流誘発のスピン刺激を行う.
STM探査機の先端と原子回転の間の磁気相互作用により, 前進を調整する.

主要な成果:

結合された原子の自律的進化をリアルタイムで追跡できました
ラルモアの周波数が一致するときにのみ, 絡み合いと角運動量交換が起こることを示した.
電子スピン散乱の場所の証拠を提供した.

結論:

この研究は,スピンの絡み合いとダイナミクスのためのラモア周波数のマッチングの重要な役割を明らかにしています.
この発見は電子のスピン散乱メカニズムに根本的な洞察をもたらします
この研究は,スピン格子における制御された量子状態の移行に関する将来の研究のための基礎を築きます.

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