Development of the and control of decoherence based on genetic algorithm

到目前为止，我们已经研制出一种名为APM的相控光源，可以在阿秒尺度上操纵物质的量子相，并成功地将APM应用于气相中孤立分子的相干控制，获得了超高的精度。为了将这种相干控制应用于凝聚相，需要控制退相干。消相干是一种在系统与环境的相互作用中失去相干性的现象。这不仅从相干控制的观点来看是重要的，而且从关于量子经典边界的基本观点来看也是重要的。人们还不能很好地理解，在原子和分子尺度上的物质中非常常见的相干是如何在系统复杂和庞大的情况下变得难以看到的。本研究的目的是利用APM作为一种灵敏的、定量的退相干检测器来测试和控制退相干。我们进行了振动波通过…的实验在超短激光脉冲作用下，碘分子中产生的更多的CKE被强的近红外激光脉冲照射，以主动地诱导退相干。在这些实验中，我们观察到波包的量子幅度随着近红外激光脉冲的照射而降低。此外，我们还将APM应用于该系统，并观察到波包的量子位相随着红外脉冲的移动而移动。这些幅度减小和相移是通过调整红外脉冲的定时和调制其光学相位来控制的。因此，我们成功地开发了一种退相干模拟器，将强的近红外激光脉冲和APM结合起来应用于气相分子。除了这个&相干模拟器，我们一直在开发一种实验装置，类似的退相干模拟器将应用于嵌入在低温恒温器中制备的固体对氢中的碘分子。然而，我们还没有将基于遗传算法的反馈控制应用到消相干模拟器的近红外激光脉冲的相位调制中。这些努力将在该项目完成后继续进行。较少

We have so far developed a phase-controlled light source called APM to manipulate quantum phases of matter on the attosecond scale, and have successfully applied APM to the coherent control of isolated molecules in the gas phase with an ultrahigh precision. In order to apply such coherent control to condensed phases, decoherence needs to be controlled. Decoherence is a phenomenon where coherence is lost in the interaction of the system with an environment. It is important not only from a viewpoint of coherent control but also from a fundamental point of view regarding the quantum-classical boundary. It is not yet understood very well how coherence, which is dearly seen in matter on the atomic and molecular scales, becomes difficult to be seen with the system being complex and large. The purpose of the present research is to test and control decoherence by using APM to serve as a sensitive and quantitative detector of decoherence.We have carried out experiments where vibrational wave pa … More ckets generated in the iodine molecules with an ultrashort laser pulse are irradiated with an intense near infrared laser pulse to actively induce decoherence. In these experiments, we have observed that the quantum amplitudes of the wave packets have been decreased with the irradiation of the near infrared laser pulse. Moreover we have applied APM to this system and have observed that quantum phases of the wave packets have been shifted with the infrared pulse. These amplitude-decrease and phase shift have been controlled by tuning the timing of the infrared pulse and by modulating its optical phase. We have thus succeeded in developing a decoherence simulator where intense near infrared laser pulses and APM are combined to be applied to the gas-phase molecules. Apart from this &coherence simulator, we have been developing an apparatus for the experiment where similar decoherence simulator will be applied to the iodine molecules embedded in a solid para-hydrogen prepared in a cryostat. We have not yet employed, however; a feedback control based on genetic algorithm to the phase modulation of the near infrared laser pulse of the decoherence simulator. These efforts will be continued after this project. Less