Application of Pulse-Shaping and Multi-Pulse-Train for Control of Chemical Reaction in Condensed Phase and Surface

脉冲整形和多脉冲序列在凝聚相和表面化学反应控制中的应用

基本信息

批准号：
15350009
负责人：
WADA Akihide
金额：
$ 9.47万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15350009/
关键词：
pulse train optimal pulse shaping adaptive control control of excitation efficiency control of reaction coherent control low-frequency vibration mode pulse compression フェムト秒パルス光パルストレイン波形整形パルスシェイピング表面化学超高速分光遠赤外励起

项目摘要

In order to examine the potentiality of multi pulse train and pulse shaping technique for control of chemical reaction, control of excitation process and excited states of perylene crystal was investigated by optimal pulse shaping technique. We succeeded in controlling the emission spectral feature of an α-perylene crystal ; the intensity of E-emission was increased by a factor of 1.4 without the change of Y-emission intensity. Furthermore, we found a near-infrared pulse shape whose multi-photon excitation efficiency is larger than that of a single femtosecond pulse by a factor of two. It was concluded from these results that pulse train and pulse shaping technique can control excitation process of molecules in condensed phase. In order to extend the application area of the pulse-shaping technique by increasing the pulse energy, the compression of femtosecond pulses obtained from a conventional regenerative amplifier was attempted by X^<(2)>:X^<(2)> process using BBO crystals. It was r … More ealized that the pulse width of 120 fs was narrowed to about 80 fs.For the search of the molecular system which can be applied by the pulse shaping technique, the time-resolved experiments were carried out on several molecular-adsorbed-surface systems. It was found on isobutene adsorbed zeolite system that a short-lived species is produced by vibrational excitation of isobutene adsorbed OD groups. From the temporal behavior of OD band intensity, the desorption of isobutene takes places after the vibrational relaxation of OD mode finishes and before the system reaches thermal equilibrium. On the c(4×2)-CO/Ni(111) system, it was found that the site-hopping of CO molecule from hollow site to atop site was induced by the irradiation of intense near-infrared pulses. The hopping phenomenon was found to be entirely transient, with the surface returning to the pre-excited state within a few hundred picoseconds without desorption. The transient response of 10 molecular layers of D_2O ice on CO/Pt(111) at 130 K was also investigated under ultra-high vacuum following a near-infrared pump pulse by sum frequency generation (SFG) spectroscopy. It was revealed that the D_2O molecules in the ice crystalline layer formed an amorphous or liquid-like structure in response to the pumping without desorption of D_2O to the gas phase, and the crystals returned to the crystal structure on a sub-nanosecond time scale. Less

为了检查多脉冲序列和脉冲塑形技术对化学反应的控制的潜力，通过最佳脉冲塑形技术研究了对兴奋过程的控制和perylene晶体的激发态。我们成功地控制了α-深油晶体的发射光谱特征。 E-Susion的强度增加了1.4倍，而不会改变Y发射强度。此外，我们发现了一个近红外的脉冲形状，其多光子兴奋效率大于单秒脉冲的脉冲效率大于两个脉冲。从这些结果得出的结论是，脉冲序列和脉冲成型技术可以控制凝结相分子的兴奋过程。为了通过增加脉冲能量来扩展脉冲成形技术的应用区域，使用X^<（2）>：X^<（2）>使用BBO晶体进行过程。 r…更加了解了120 FS的脉冲宽度狭窄到约80 fs。搜索可以通过脉冲成型技术应用的分子系统的搜索，时间分辨的实验是在几个分子吸附的 - 添加标准表面系统上进行的。在异丁烯吸附的沸石系统上发现了一个短暂的物种是通过异丁烯吸附OD基团的振动兴奋而产生的。从OD带强度的暂时行为，异丁烯的解吸发生在OD模式饰面的振动松弛和系统达到热平衡之前。在C（4×2）-Co/Ni（111）系统上，发现从空心位点到位于位置的CO分子的位置跃迁是通过强烈的近红外脉冲的照射引起的。发现跳跃现象是完全瞬态的，表面返回了几百张picseconds的预兴趣状态，而无需解吸。还通过总和频率产生（SFG）光谱检查了在超高真空下，在130 K上的10个分子层D_2O ICE（111）上的10个分子层D_2O ICE（111）的瞬态响应。据揭示，冰晶层中的D_2O分子响应泵送而在不解吸D_2O到气相的情况下形成了无定形或液体样结构，并且晶体以次纳米秒的时间尺度返回到晶体结构。较少的