Manipulating photon-atom interactions with atomic coherence and interference

本实验研究项目研究激光光场与多能级原子系统的相干相互作用引起的原子相干和干涉，并探索其在非线性光学和量子光学中的应用。将开发两种实验方法并在研究计划中使用。在第一种方法中，将探索原子和光子的量子态操纵和控制，其中冷原子被限制在光腔中。研究了相干驱动冷原子中腔增强的非线性混频和腔内暗态辅助的慢光传输。原子-腔系统也将被用来研究光子转换和光子关联。在第二种方法中，我们将研究自由空间中冷原子的量子非线性光学。将研究双通道四波混频，并将其用于探索纠缠和关联光子对的产生。我们将研究电磁感应透明所表现出的大的克尔非线性和交叉相位调制。此外，还将研究相干制备的三能级和四能级系统中的多光子量子干涉，并将其用于通过操纵弱控制场的幅度和相位来探索光控制光的应用。这些实验研究将导致新现象的发现，并有助于超弱光强下的基本量子光学和非线性光学的发展。它还将导致控制原子和光子量子态的新技术的发展，这将有助于量子测量和量子信息网络的应用。拟议的研究采用先进的实验方法和复杂的光谱测量，为研究生和本科生提供与研究相关的教育和培训机会，使他们能够为追求科学事业发展科学知识和技术技能。

This experimental research program studies atomic coherence and interference induced by coherent interactions between laser fields and multi-level atomic systems, and explore its applications in nonlinear optics and quantum optics. Two experimental approaches will be developed and used in the research program. In the first approach, quantum state manipulation and control of atoms and photons with cold atoms confined in an optical cavity will be explored. The cavity enhanced nonlinear wave mixing in coherently driven cold atoms and slow light propagation assisted by the intra-cavity dark state will be studied. The atoms-cavity system will also be used to study photon switching and photon correlations. In the second approach, quantum nonlinear optics will be studied with cold atoms in free space. Two-channel four-wave mixing will be studied and used to explore generation of entangled and correlated photon pairs. Large Kerr nonlinearities and cross-phase modulation manifested by electromagnetically induced transparency will be investigated. Also the multi-photon quantum interference in coherently prepared three-level and four-level systems will be studied and used to explore applications of light control light by manipulating the amplitude and phase of a weak control field. These experimental studies will lead to discoveries of new phenomena and contribute to the advancement of fundamental quantum optics and nonlinear optics at ultra-low light intensities. It will also lead to the development of new techniques to control the quantum states of atoms and photons, which will be useful for applications in quantum measurements and quantum information network. The proposed research implements advanced experimental methods and sophisticated spectroscopic measurements, which offers research related education and training opportunities for graduate and undergraduate students and enable them to develop scientific knowledge and technical skills for their pursuit of scientific careers.