Altering the Course of Quantum Dynamics Phenomena

Princeton University, Princeton NJ

Investigators

Abstract

With this award, the Chemical Theory, Models and Computational Methods (CTMC) Program in the Chemistry Division is supporting Professor Hershel Rabitz of Princeton University to conduct theoretical studies on the control of quantum dynamics in molecules. This award is cofunded by two other programs in the Chemistry Division; namley Chemical Structure Dynamics and Mechanisms-A (CSDM A) and Chemical Measurement and Imaging (CMI). Ever since lasers were invented in the 1960's, scientists have speculated that it may someday be possible to use these special light sources to manipulate molecules and even selectively break chemical bonds. This prospect holds out promise of essentially "performing laser surgery" on molecules, whereby one portion of the molecule is altered while simultaneously leaving other areas untouched. The research in the Rabitz laboratory seeks to begin to lay the foundation for this vision to become a practical reality. The effort involves theoretical studies establishing the key principles for the creation of laser designs affecting precise manipulation of molecules. The theoretical principles take into consideration both the nature of laboratory laser resources as well as the structure and other features of molecules and how they interact with laser light. The outcome of this research is expected to provide a more thorough understanding of laser-molecule interactions and the practical attainable molecular goals lying ahead in the coming years using advanced laser light resources. Students trained in the Rabitz laboratory receive a high broad and highly inter-disciplinary education. The discovery of tailored laser pulses capable of achieving specific manipulations of molecules is performed as an optimization process working within the laws of quantum mechanics. Professor Rabitz aims to explore the features of what is called the quantum control landscape, which is the molecular observable property of interest as a function of the laser control field. The structure of these landscapes is essential to understand, as the search for an optimal control field entails a climb of the landscape to the highest attainable chemical product yield. The possible presence of complex hindering features on the landscape could impede such searches. Rabitz and coworkers develop special theoretical tools to reveal the true landscape structure and explore its implications for practical laser control of molecules. Concomitantly, the team will develop theoretical tools to investigate the mechanisms by which laser fields manipulate quantum dynamics phenomena including for chemical bond-breaking. Moreover, the mechanistic studies performed by the Rabitz group aim to lay a foundation for extracting physical models of laser driven dynamics extracted from experimental data.