Cooling of Atoms in Optical Cavities by Collective Dynamics

驻波光中的原子经历一种称为光学晶格的周期性势。近年来，光学晶格中冷原子的研究已成为冷原子物理的一个重要前沿。我们建议打开一个新的领域，这项研究中有驻波的光学腔。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，腔体内的集体效应可以将大量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]和第一个不完整的实验研究[3，4，5]所示，在存在红失谐激光场的情况下，当腔泄漏率与N乘以单粒子耦合常数的平方根一样大时，预期会有最大的冷却速率。描述粒子在光学晶格势中运动的声子随后被连续地转换成光子，光子通过腔镜泄漏出去。其结果是系统中的动能在时间尺度上的蒸发，该时间尺度由通过谐振腔反射镜的光子的非常大的泄漏率给出。我们建议研究这些非线性量子系统中自然发生的冷却和相关的集体效应，并将实验结果与详细的和新开发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开始对这些效应的研究，汇集冷原子，腔QED，量子物理学，许多身体系统和非线性动力学的专业知识。[1]A. Beige，P.L. Knight和G. Vitiello，Cooling Many Particles at Once，New J. Phys. 7，96（2005）。[2]A. Beige，P.L. Knight和G. Vitiello，冷却许多粒子到非常低的温度，Braz。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.陈晓，原子在光腔中的集体辐射诱导冷却，物理学报，2000。90，063003（2003）。[5]与Ph. Grangier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.