对于强烈相互作用的玻色子的卢廷格尔液体,钉定量子相位过渡
Elmar Haller1, Russell Hart, Manfred J Mark
1Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria.
Nature
|July 31, 2010
概括
研究人员在一维的超冷气体中观察到一种新的量子相位过渡. 一个弱的光学晶格诱导了强烈相互作用的玻色子原子从超流体到Mott绝缘体的过渡.
科学领域:
- 量子物理学的量子物理学
- 凝聚物质物理学 凝聚物质物理学
- 超冷的原子气体是超冷的原子气体.
背景情况:
- 量子多体系统表现出由量子波动驱动的零温度相位过渡.
- 超流体中的Mott-Hubbard过渡到绝缘体在弱相互作用系统中是已知的.
- 强烈相互作用的低维系统可能会经历由弱扰动引起的新型转变.
研究的目的:
- 通过实验观察和描述一维超冷气体中的新型量子相位过渡.
- 为了研究从超流体卢廷格液体到莫特绝缘体的正弦-戈登量子相位过渡.
- 绘制相位图并将实验结果与理论模型进行比较.
主要方法:
- 使用 bosonic cesium 原子的一维量子气体,具有可调节的相互作用.
- 应用了微弱的光学晶格扰动来诱导量子相位过渡.
- 测量了相位图,并将结果与正弦-戈登和一维波斯-哈巴德模型进行了比较.
主要成果:
- 成功观察到正弦-戈登量子相位过渡从超流体的卢廷格液体到莫特绝缘体.
- 发现弱光学格子可以在强烈相互作用的系统中诱导这种过渡.
- 强相互作用模式中的实验数据与正弦-戈登模型很好地一致,而弱相互作用模式中的实验数据与斯-哈巴德模型一致.
结论:
- 这项研究证明了一种新型的量子相位过渡,由强烈相互作用的低维系统中的微弱扰动驱动.
- 这些发现验证了基于正弦-戈登和斯-哈巴德模型的理论预测.
- 开辟了量子关键性和运输现象的实验研究的途径,超出了使用超冷气体的传统模型.
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