Ultracold bosonic gases coupled to an optical cavity mode

超冷玻色子气体耦合到光学腔模式

• 批准号: 299282899
• 负责人: Professorin Dr. Corinna Kollath
• 金额: --
• 依托单位: Physikalisches Institut
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/299282899?language=en
• 关键词: Ultracold; bosonic; gases; coupled; optical

Ultracold atoms coupled to a photonic mode of an optical cavity show fascinating phenomena such asthe Dicke phase transition. This is a self-organized phase transition in which the atoms spontaneouslyorder into a checkerboard density pattern and the photonic mode becomes occupied due to thefeedback mechanism between the atoms and the photonic mode. In this project we will investigatebosonic atoms which are coupled to photonic modes and are additionally confined to optical latticestructures. We will mainly focus on a novel coupling dominantly to the tunneling process of the atomswith or without spatially dependent phase imprint which has been proposed by the PI. We expectinteresting phases to occur such as the self-organization of complex Mott-insulating and superfluidphases or in the presence of a phase imprint, Meissner and vortex phases.The full solution of the dynamics of the combined atom-cavity system is very demanding mainlydue to three reasons: (i) the strongly correlated nature of the interacting bosonic atoms in optical lat-tices, (ii) the coupling of the spatially extended cavity mode to the atoms, which can induce effective,long-range interactions between the atoms, and (iii) the dissipative nature of the cavity mode by theleaking of the photons out of the cavity due to imperfect mirrors. We describe the combined and dis-sipative system by a Markovian master equation with a Lindblad dissipator. In order to determine theresulting dynamics we will employ different approaches. In a first approach, we will reduce the modelby adiabatically eliminating the cavity mode to an effective interacting bosonic model - with long-rangeprocesses - subjected to a self-consistency condition. For the solution of this self-consistent modelwe will develop a self-consistent implementation of the matrix product state (MPS) algorithm andthe quantum Monte-Carlo method in collaboration with project P6. The second approach aims at afull numerical simulation in quasi-one-dimensional systems. The implementation of a time-dependentMPS taking into account the dissipative and extended cavity mode with a large local Hilbert space isone of the main challenges of the project.

超冷原子耦合到光腔的光子模中，表现出诸如迪凯相变等有趣的现象。这是一种自组织相变，在这种相变中，原子自发地有序排列成棋盘状的密度模式，由于原子和光子模之间的反馈机制，光子模被占据。在这个项目中，我们将研究与光子模耦合的玻色子原子，并将其限制在光学晶格结构中。我们将主要研究PI提出的一种新的以原子隧穿过程为主导的耦合，这种耦合有无空间相关的相位印记。我们期待有趣的阶段发生，如复杂的莫特绝缘和超流体相的自组织，或在相印记，迈斯纳和涡旋相的存在下。原子-腔组合系统的动力学的完整解决方案是非常苛刻的，主要是由于三个原因：（i）光晶格中相互作用玻色子原子的强关联性质，（ii）空间扩展的腔模与原子的耦合，这可以诱导原子之间有效的长程相互作用，以及（iii）由于不完美的反射镜导致光子从腔中泄漏出来，从而导致腔模的耗散性质。我们用一个带有Lindblad算子的马尔可夫主方程来描述这个组合耗散系统。为了确定所产生的动态，我们将采用不同的方法.在第一种方法中，我们将减少模型通过示意性地消除腔模式到一个有效的相互作用玻色子模型-与long-rangeprocesses -服从自洽条件。对于这个自洽模型的解决方案，我们将与项目P6合作开发一个矩阵乘积态（MPS）算法和量子蒙特-卡罗方法的自洽实现.第二种方法旨在准一维系统中的完整数值模拟。该项目的主要挑战之一是实现一个考虑耗散和扩展腔模式的时间相关MPS，并具有较大的局部希尔伯特空间。