射频吸收法测阱中N_2^+离子的动力参数

Measurement of Kinetic Parameters of N_2^+ Ions in a Paul Trap by RF Absorption Detection

利用射频吸收检测,测量了射频阱中N_2^+离子总数随外加直流电压的变化,据此求得了高斯分布下的离子云平均宽度和平均动能,结果与Brown运动模型得出的理论值符合,并与现有的均匀球分布的结果进行了比较。

We measured variations of the total number of N_2^+ ions in a Paul trap versus applied dc voltage, and accordingly derived the mean kinetic energy and mean width of the spatial distribution of the ion cloud under the assumption of Gaussian model. The results are consistent with the theoretical values obtained from model calculations based on Brownian motion of trapped ions, and also compared with those derived by assuming uniform sphere distribution of ions.