PSEUDOPOTENTIAL METHOD IN COLD ATOM RESEARCH

C. N. Yang

C. N. Yang

Chongming Yang

Yang Liu, Zhenjie Shen, X. Wang +1 more

With the continuous advancement and maturation of laser cooling techniques for atoms and molecules and full-dimensional electron and ion imaging technology, using momentum imaging techniques to investigate the characteristic properties of cold atoms and collision dynamics has emerged as a burgeoning research direction. This progress has driven the development of a series of high-resolution electron and ion detection devices, leading to innovative breakthroughs in fields such as cold molecule reactions, Rydberg atoms, nuclear decay, photoionization of Bose-Einstein condensates (BECs) and cold plasmas, collisions between cold atoms and ions/electrons, coherent control of cold atoms, and strong-field ultrafast physics. This article reviews representative instruments and their corresponding seminal achievements in the following domains: In cold molecular/cold chemical reactions, imaging technology has revealed new insights into reaction mechanisms; For cold Rydberg atom interactions, it demonstrates high-precision quantum state manipulation capabilities, advancing quantum information processing; In nuclear decay research, it provides ultra-sensitive detection methods, deepening understanding of decay processes; For BEC photoionization and cold plasma control, it can precisely monitor and manipulate microscopic processes; In cold atomic collision studies, it reveals new details in collision dynamics, refining collision theories; Regarding coherent control of cold atoms, it achieves accurate quantum state manipulation and interference; In strong-field ultrafast processes, it elucidates complex electron dynamics under intense fields, providing innovative methods for ultrafast laser control. Furthermore, this article summarizes the applications of imaging technologies in the aforementioned research areas involving cold atoms, and provides prospects for future developments in this evolving field.

Li Li, Yi-Jia Liu, Xiaolong Zhou +6 more

Optical traps, including those used in atomic physics, cold chemistry, and quantum science, are widely used in the research on cold atoms and molecules. Owing to their microscopic structure and excellent operational capability, optical traps have been proposed for cold atom experiments involving complex physical systems, which generally induce violent background scattering. In this study, using a background-free imaging scheme in cavity quantum electrodynamics systems, a cold atomic ensemble was accurately prepared below a fiber cavity and loaded into an optical trap for transfer into the cavity. By satisfying the demanding requirements for the background-free imaging scheme in optical traps, cold atoms in an optical trap were detected with a high signal-to-noise ratio while maintaining atomic loading. The cold atoms were then transferred into the fiber cavity using an optical trap, and the vacuum Rabi splitting was measured, facilitating relevant research on cavity quantum electrodynamics. This method can be extended to related experiments involving cold atoms and molecules in complex physical systems using optical traps.

Yiran Yin, An‐Ning Xu, Bei Liu

ABSTRACT Dual‐species cold atom systems are drawing increasing attention in the research of interactions in degenerate cold gases. In this article, we report a method for the simultaneous cooling of 85 Rb and 87 Rb atoms in an integrating sphere system. Optimal parameters were determined for cooling laser power and cooling laser detuning to maximize the number of cold atoms and minimize the collision‐induced loss rate coefficients. The 87 Rb atoms at a temperature of 82 with an atomic number of , and 85 Rb atoms at a temperature of 87 with an atomic number of are simultaneously cooled. Our results offer an approach for the simultaneous cooling of two‐isotope mixtures, featuring a large atomic number, low temperature, and no requirement for an external magnetic field. This method holds significant potential for applications in quantum precision measurement, such as gravity gradiometers and cold atomic magnetometers.