【摘要】 本文报道了用激光选择性探测少数约原子的共振双光子电离实验,铯原子的光电离达到了完全饱和,每一个激光脉冲探测到的原子数为5.3×10⁴。使用一台可调频染料激光器完成了铯原子的共振双光子电离,第一个光子使Cs原子从基态6²S_1/2激发到7²P_1/2能级,第二个光子使Cs原子离化。本实验采用自建的消融灯泵浦的脉冲染料激光强迫振荡器,输出线宽为0.5（?）,波长4593（?）,能量为300mJ,脉宽2μs,激光束被聚焦到原子束池中,能量密度始终保持大于1J/cm²,电离后的离子电子对由静电计检测。为了与实验值比较,假设对一个简易的计算模型进行了理论计算,实验值与理论值很好地符合。更多还原

【Abstract】 The two-photon resonance ionization experiment for the detection of ultra-low concentration of atomic cesium is described. Complete saturation of photoionization was achieved. The number of atoms detected with each laser pulse was measured to be 5.3?l04.By using a tunable dye laser we have achieved the two-photon resonance ionizations the first photon excited cesium atom from ground state 62S1/2 to the excited state 72P1/2, and the second photon ionized the excited cesium atom.In this experiment we have used a home-made ablating-wall flashlamp pumped pulsed dye laser forced oscillator, the output linewidth was 0.5A, wavelength 4598 A, pulse energy 300 mJ, and pulse width 2 ?s. The laser beam was focused to the region where atomic beam interacted with it. The energy density in this region was always kept greater than 1 J/om2. The ionized ion-electron pair was detected by the electrometer.The experimental value was compared with a theoretical calculation which gave a simple calculation model. The experimental results agreed very well with the theoretical calculations.更多还原