一种针对弱场搜寻态冷极性分子的可控静电表面囚禁方案

doi:10.19596/j.cnki.1001-246x.7556

摘要/Abstract

摘要： 提出一种使用带电金属环和六个球电极和一个外加偏置电场实现对冷极性分子静电囚禁的新方案.计算装载和囚禁时空间电场分布.囚禁中心距离芯片表面的高度可以通过外电场和环形电极所加电压来操控.蒙特卡罗模拟表明对于中心速度为15 m·s^-1的ND₃分子束，装载效率可以达到70%，得到冷分子的温度大约为45 mK.当继续增加偏置电场强度时，单阱分裂为对称的两个阱.如果同时改变球形电极上所加电压，得到不对称的两个阱，可以借此来调节两个阱中所囚禁的冷分子数目的比例.为了易于理解，用蒙特卡罗方法模拟了装载、囚禁、分裂冷分子波包的动力学过程.

关键词: 冷极性分子, 静电表面囚禁, 蒙特卡罗模拟

Abstract: A novel electrostatic surface trap for cold polar molecules with an insulator-embedded charged ring and six charged spherical electrodes together with a bias electric field is proposed. Distributions of electric field in loading and trapping are calculated. Distance between trap center and chip surface are controlled conveniently with bias electric field and voltage applied to the ring electrode. For ND₃ molecular beam centered at ~15 m·s^-1, a loading efficiency as high as 70% is obtained. Corresponding temperature of trapped molecules is about 45 mK. As bias electric field is continued to increase, the single well splits into two identical ones. If voltages applied to spherical electrodes are changed in the meanwhile, two different wells are generated. Number ratio of molecules trapped in two wells can be adjusted. Dynamic processes of loading, trapping and splitting were simulated with classical Monte Carlo simulations.

Key words: cold polar molecules, electrostatic surface trap, Monte Carlo simulation

中图分类号:

O561

李胜强. 一种针对弱场搜寻态冷极性分子的可控静电表面囚禁方案[J]. 计算物理, 2017, 34(6): 731-739.

LI Shengqiang. A Controllable Electrostatic Well for Cold Polar Molecules in Weak Field Seeking State on a Chip[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2017, 34(6): 731-739.

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