Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USADepartment of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA.
Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
J Chem Phys. 2019 Jan 28;150(4):044303. doi: 10.1063/1.5070067.
Quantum coherent control (QCC) has been successfully demonstrated experimentally and theoretically for two- and three-photon optical excitation of atoms and molecules. Here, we explore QCC using spectral phase functions with a single spectral phase step for controlling the yield of H from methanol under strong laser field excitation. We observe a significant and systematic enhanced production of H when a negative 34 π phase step is applied near the low energy region of the laser spectrum and when a positive 34 π phase step is applied near the high energy region of the laser spectrum. In some cases, most notably the HCO fragment, we found the enhancement exceeded the yield measured for transform limited pulses. The observation of enhanced yield is surprising and far from the QCC prediction of yield suppression. The observed QCC enhancement implies an underlying strong field process responsible for polyatomic fragmentation controllable by easy to reproduce shaped pulses.
量子相干控制（QCC）已在双光子和三光子激发原子和分子的实验和理论中得到成功验证。在这里，我们使用具有单个光谱相位阶跃的光谱相位函数来控制在强激光场激发下甲醇中 H 的产率。我们观察到当在激光光谱的低能区附近施加负的 34π 相位阶跃，而当在激光光谱的高能区附近施加正的 34π 相位阶跃时，H 的产量会显著且系统地增强。在某些情况下，尤其是 HCO 碎片，我们发现增强的幅度超过了对变换限制脉冲测量的产量。观察到的增强产量令人惊讶，与 QCC 对产量抑制的预测相去甚远。所观察到的 QCC 增强表明存在一种强场过程，负责多原子碎片，这种过程可以通过易于复制的整形脉冲来控制。
