Coherent superposition of M-states in a single rovibrational level of H2 by Stark-induced adiabatic Raman passage.
Coherent superposition of M-states in a single rovibrational level of H2 by Stark-induced adiabatic Raman passage.
复制标题
Stark 诱导的绝热拉曼通道在 H2 的单个旋转水平中 M 态的相干叠加。
作者：
N. Mukherjee;Wenrui Dong;R. Zare
利用斯塔克诱导绝热拉曼通道，在532 nm，脉宽为1.6 ns，200 mJ/pulse的线偏振单模泵浦和699 nm，脉宽为1.4 ns，20 mJ/pulse的斯托克斯激光激发下，制备了一个处于磁性子能级M的锁相叠加态的孤立旋振激发（v = 1，J = 2）H2分子系综.利用线偏振但交叉偏振的抽运脉冲和Stokes激光脉冲沿量子化z轴沿着共同传播，制备了一个双轴叠加态：[line] v（t）= 1/（2）[[line] v = 1，J = 2，M = -2- [line] v = 1，J = 2，M = +2].相位相干度通过使用H2 E，F-X（0，1）带的O（2）线经由2 + 1共振增强多光子电离（REMPI）在210.8 nm处测量，通过在飞行时间质谱仪中记录REMPI信号中的干涉条纹，同时使用半波片旋转UV激光偏振的方向。当Stokes频率调谐到（v = 0，J = 0）→（v = 1，J = 2）拉曼共振时，从E，F-X（0，0）带的Q（0）线的耗尽测量到近60%的粒子数从H2（v = 0，J = 0）基态转移到H2（v = 1，J = 2）的叠加态.
We prepare an ensemble of isolated rovibrationally excited (v = 1, J = 2) H2 molecules in a phase-locked superposition of magnetic sublevels M using Stark-induced adiabatic Raman passage with linearly polarized single-mode pump (at 532 nm, ∼6 ns pulse duration, 200 mJ/pulse) and Stokes (699 nm, ∼4 ns pulse duration, 20 mJ/pulse) laser excitation. A biaxial superposition state, given by [line]ψ(t)⟩ = 1/√(2)[[line]ν = 1, J = 2, M = -2⟩ - [line]ν = 1, J = 2, M = +2⟩], is prepared with linearly but cross-polarized pump and Stokes laser pulses copropagating along the quantization z-axis. The degree of phase coherence is measured by using the O(2) line of the H2 E,F-X (0,1) band via 2 + 1 resonance enhanced multiphoton ionization (REMPI) at 210.8 nm by recording interference fringes in the REMPI signal in a time-of-flight mass spectrometer as the direction of the UV laser polarization is rotated using a half-wave plate. Nearly 60% population transfer from H2 (v = 0, J = 0) ground state to the superposition state in H2 (v = 1, J = 2) is measured from the depletion of the Q(0) line of the E,F-X (0,0) band as the Stokes frequency is tuned across the (v = 0, J = 0) → (v = 1, J = 2) Raman resonance.