Cooling of Atoms in Optical Cavities by Collective Dynamics

驻波光中的原子经历一种被称为光学晶格的周期性势能。在过去的几年里，光学晶格中冷原子的研究已经成为冷原子物理学的一个主要前沿。我们建议通过将驻波放在光学腔中来打开这项研究的新领域。这有望通过原子与单光子模式的共同耦合来诱导新的集体效应。例如，我们预计，腔内的集体效应有望将大量N个原子或分子冷却到非常低的温度。正如我们最初的理论[1，2]和第一次不完全的实验研究[3，4，5]所表明的那样，当存在红色失谐的激光场，并且腔体泄漏率大到N的平方根乘以单粒子耦合常数时，预期的最大冷却速率。声子描述了光学晶格势中粒子的运动，然后被连续转换成光子，光子通过腔镜泄漏出来。其结果是系统中的动能在一个时间尺度上蒸发，该时间尺度由通过谐振镜的非常大的光子泄漏率所给出。我们建议研究这些非线性量子系统中自然产生的冷却和相关的集体效应，并将实验结果与详细的和新发展的理论模型进行比较。该提案的目的是通过实验者和理论家的合作，汇集冷原子、腔QED、量子物理、许多身体系统和非线性动力学方面的专业知识，开始对这些效应的研究。[1]A.Beige，P.L.Knight和G.Vitiello，一次冷却多个粒子，New J.Phys。7，96(2005)。[2]A.Beige，P.L.Knight和G.Vitiello，将许多粒子冷却到非常低的温度，布拉兹。J.Phys.35,403(2005)。[3]J.F.Roch，K.Vigneron，P.Grelu，A.Sinatra，J.P.Poizat，和P.Grangier，《使用冷陷原子的量子非拆除测量》，物理。莱特牧师。78,634(1997)。[4]陈华伟，A.T.布莱克，和V.Vultic，光学腔中原子集体发射诱导冷却的观察，物理。莱特牧师。90,063003(2003年)。[5]与格兰杰博士的私人交流。

Atoms in a standing wave of light experience a periodic potential called an optical lattice. The study of cold atoms in an optical lattice has become a major frontier of cold atom physics over the last few years. We propose to open a new domain of this study by having the standing waves within an optical cavity. This is expected to induce new collective effects through the common coupling of the atoms to a single photon mode. For example, we anticipate that collective effects within a cavity can be expected to cool a large number N of atoms or molecules to very low temperatures. As our initial theoretical [1,2] and first incomplete experimental studies [3,4,5] show, maximum cooling rates are expected in the presence of a red-detuned laser field and when the cavity leakage rate is as large as the square root of N times the single-particle coupling constants. The phonons, describing the movement of the particles inside the optical lattice potential, are then continuously converted into photons, which leak out through the cavity mirrors. The result is an evaporation of the kinetic energy in the system on a time scale given by the very large leakage rate of photons through the resonator mirror. We propose to study the cooling and related collective effects that are expected to occur naturally in these nonlinear quantum systems and to compare experimental results with detailed and newly developed theoretical models. The aim of the proposal is to begin a study of these effects through a collaboration of experimenters and theorists, bringing together expertise in cold atoms, cavity QED, quantum physics, many body systems and non-linear dynamics. [1] A. Beige, P.L. Knight, and G. Vitiello, Cooling Many Particles at Once, New J. Phys. 7, 96 (2005).[2] A. Beige, P.L. Knight, and G. Vitiello, Cooling many particles to very low temperatures, Braz. J. Phys. 35, 403 (2005).[3] J. F. Roch, K. Vigneron, P. Grelu, A. Sinatra, J. P. Poizat, and P. Grangier, Quantum Nondemolition Measurements using Cold Trapped Atoms, Phys. Rev. Lett. 78, 634 (1997). [4] H. W. Chan, A. T. Black, and V. Vuletic, Observation of Collective-Emission-Induced Cooling of Atoms in an Optical Cavity, Phys. Rev. Lett. 90, 063003 (2003).[5] Private communication with Ph. Grangier.