论文标题
拉曼速度过滤器作为共线激光光谱的工具
Raman velocity filter as a tool for collinear laser spectroscopy
论文作者
论文摘要
热离子束的速度分布可以用狭窄的刺激拉曼过程过滤，以制备更冷的地下，如该理论分析所证实。使用两个反向传播的远程激光器，我们可以定义一个$π$ -Pulse，用于谐振速度，以在$λ$系统的地面之间的拉曼共振的线宽内传递原子。来自两个单光子共振的自发发射以及激光噪声引起的基态反应，降低了滤波器的效率。从综合的主方程中，我们获得了激光器最佳频率对的条件，并通过数值和分析来评估滤波器性能。如果我们将此分析应用于当前的$^{40} $ CA $^+$ ion实验，我们会获得一种敏感性，用于测量PPM级别或更低的高离子加速度电压。
The velocity distribution of a hot ionic beam can be filtered with a narrow stimulated Raman process to prepare a colder subensemble, as substantiated in this theoretical analysis. Using two counter-propagating, far-detuned lasers, we can define a $π$-pulse for the resonant velocity to transfer atoms within the linewidth of the Raman resonance between the ground-states of a $Λ$-system. Spontaneous emission from the two single-photon resonances, as well as the ground-state decoherence induced by laser noise, diminishes the efficiency of the filter. From a comprehensive master equation, we obtain conditions for the optimal frequency pair of the lasers and evaluate the filter performance numerically, as well as analytically. If we apply this analysis to current $^{40}$Ca$^+$ ion experiments, we obtain a sensitivity for measuring high ion acceleration voltages on the ppm level or below.
