超伝導量子ビットによって検出された個々の原子トンネルシステムのストレントーニング
Grigorij J Grabovskij1, Torben Peichl, Jürgen Lisenfeld
1Physikalisches Institut and Deutsche Forschungsgemeinschaft Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany.
Science (New York, N.Y.)
|October 16, 2012
まとめ
研究者らは,超伝導量子ビットの酸化物障壁の変形が原子トンネルシステムを変化させることを発見しました. この相互作用は,マイクロ波光譜を用いて測定され,無秩序な固体における重要な仮説が確認されました.
科学分野:
- 量子力学は,量子力学という
- 凝縮物質物理学 凝縮物質物理学
- マテリアルサイエンス 材料科学
背景:
- 構造的に無秩序な固体は,低温の異常の原因となる原子トンネルシステムを示している.
- これらのシステムはまた,特にジョセフソン交差点の酸化物バリアの内部では,超伝導クビットの脱コエレンスを引き起こします.
研究 の 目的:
- 不規則な固体における原子トンネルシステムに対する微小な変形の影響を実験的に調査する.
- これらのシステムのエネルギーの変化を測定するために,超伝導量子ビットを敏感な探査機として使用します.
主な方法:
- 超伝導クビットを使用して,一貫した相互作用を通じて原子トンネルシステムを探査します.
- マイクロ波スペクトロスコピーを用いて,外部ストレスの下にある原子トンネル状態のエネルギー分裂変化を測定する.
- ジョセフソン交差点の酸化物バリアに微小な変形を引き起こします.
主要な成果:
- オキシードバリアのわずかな変形が,原子トンネルシステムのエネルギーを測定可能なほど変化させることを実証した.
- 量子ビットの反応をマイクロ波スペクトロスコピーで観察することで,これらのエネルギーシフトを測定することに成功しました.
- 外部負荷と原子トンネル状態のエネルギー分裂との相関を確立した.
結論:
- 実験結果は,無秩序な固体のための2階トンネリングモデルの中心的な仮説を検証しています.
- 超伝導量子ビットは,無秩序な物質の量子現象を研究するための正確なツールとして機能することができます.
- 原子トンネルシステムの理解と制御は,量子ビットの一貫性を改善し,基本的な物理学の探索に不可欠です.
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