メカニカルオシレータの熱失調率の測定ベースの制御
D J Wilson1, V Sudhir1, N Piro1
1Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Nature
|August 11, 2015
まとめ
量子フィードバック制御のための新しい位置センサーを開発しました. このセンサーは前例のない精度で ナノメカニカルオシレータを 基本状態に近い状態まで冷却し 巨大な物体の量子制御の道を開きます
科学分野:
- 量子物理学
- オプトメカニクス
- ナノテクノロジー
背景:
- リアルタイム量子フィードバックプロトコルは 連続的な測定記録を使って 量子状態を安定させます
- 微波光子や超伝導量子ビットのような 微小システムでも成功しています
- 機械的な振動器のような 巨大な物体を安定させることは 環境の不協和性のために 難しいことです
研究 の 目的:
- ナモメカニカルオシレータのゼロポイント運動を解明できる位置センサーを開発する.
- 量子フィードバックをリアルタイムで制御する
- 巨大な量子システムにおける 環境の不協和によって 課される制限を克服する
主な方法:
- 高Q微小穴への光学結合
- 高精度で低不精度反作用の位置センサの開発
- 放射圧によるフィードバック冷却のためのエラー信号としてセンサを使用します.
主要な成果:
- センサーは,4.3MHzのナモメカニカルオシレータのゼロポイント運動を,その熱的脱合時間スケール内で解明します.
- 標準量子限界より4倍の不精度で 100倍改善した
- 振動器を4. 4Kから1.1 ± 0. 1mKに冷却し, 16%の基底状態の確率を達成した.
結論:
- 開発されたセンサーは,線形位置感知のための新しい基準を設定します.
- 量子フィードバック制御の実現可能性を示している.
- 量子制御のための実用的なシステムとして 機械的な振動器の出現を示しています
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