有效质量法调控原子玻色-爱因斯坦凝聚体的双阱动力学

发布时间：2018-02-14 08:26

本文关键词： 玻色-爱因斯坦凝聚有效质量双势阱光晶格约瑟夫森动力学　出处：《华东师范大学》2017年硕士论文　论文类型：学位论文

【摘要】：原子的玻色爱因斯坦凝聚作为一种先被理论预言后被实验验证的宏观量子力学现象,一直是物理领域的热点之一。玻色-爱因斯坦凝聚良好的量子相干现象促使其成为众多领域的研究对象或研究工具,在这些研究中通过磁、光构建势场来精密操控原子凝聚体是必不可少的研究手段。利用束缚在双阱势场中原子凝聚体来模拟约瑟夫森超导结,是一个十分典型的量子模拟研究.传统方法通过操控形成双势阱的磁场或利用费许巴赫共振法调节凝聚原子相互作用强度,可以使凝聚体展现量子隧穿振荡或自束缚等典型的约瑟夫森结动力学。本文提出了通过光晶格调节原子凝聚体有效质量,从而控制凝聚体在双阱势中动力学行为的方案。在平均场近似下,我们导出了系统的动力学方程。数值模拟发现,改变有效质量,可以使凝聚体在双阱中的动力学行为由量子隧穿占主导的简谐振荡向原子碰撞占主导的自束缚的转变。即有效质量变化导致的系统能量的改变。我们还讨论了负有效质量的情形,发现他可以用来模拟负散射长度原子凝聚体的动力学。与直接调整形成双阱的束缚场或用Feshbach共振法调节原子相互作用的传统方案不同,本方案对一些要求固定束缚条件的凝聚体研究或是对磁场调节不敏感的原子较有意义。
[Abstract]:Bose Einstein condensation of atoms as a first experimental verification of the theoretical predictions by macroscopic quantum mechanical phenomena, has been one of the hot areas of physics. Bose Einstein condensates good quantum interference phenomenon to become the object of study or research tool in many fields, in these studies by magnetic potential, light construction a precise manipulation of atom condensates is indispensable. The bound in a double well potential field in atomic condensates to simulate Joseph Sen superconducting junction, a simulation study is a very typical quantum control. The traditional method through the formation of double well magnetic field or by Fisher Bach resonance method regulating condensed atom interaction the strength, can make the condensate show quantum tunneling oscillation or self bound typical Josephson node dynamics. This paper proposes effective aggregate quality by adjusting the atomic optical lattice, Dynamic properties in double well potential solutions to control. In the mean field approximation, we derive the dynamic equations of the system. Simulation results show that the change of effective quality, simple harmonic oscillation can make dynamic properties in double well by the quantum tunneling dominated to atomic collision dominated from bondage the change that lead to effective quality change. The change in energy system. We also discuss the negative effective mass, that he can be used to simulate the dynamics of the condensate negative atomic scattering length. Different traditional schemes regulating the atomic interaction form double well and directly adjust the bound field or Feshbach resonance method, the scheme of some fixed bound condition of the condensate or Research on magnetic field regulation is not sensitive to the atom is meaningful.

【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O469

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