Altering the Course of Quantum Dynamics Phenomena

Princeton University, Princeton NJ

Investigators

Abstract

Professor Herschel A. Rabitz of Princeton University is supported by the Chemical Theory, Models and Computational Methods Program to develop new theoretical concepts for quantum control. The control of quantum phenomena entails interceding in the normal evolution of dynamical events through the introduction of external fields. Quite surprisingly, finding optimal fields for this purpose is proving to be easier than anticipated both in simulations and in the laboratory. At Princeton, an effort has been underway to fundamentally understand the origins of this behavior. In particular, at the most basic level, the structure of the control landscape needs to be understood, where a control landscape is the physical observable as a function of the controls. A family of theoretical and computational analysis tools will be used to analyze these landscapes with the aim of ultimately providing insights into identifying the basic rules for controlling quantum phenomena. Part of this effort will include revealing the mechanisms by which control is achieved and the role of general Hamiltonian structure in facilitating control. The outcome of this research is expected to be a deeper understanding of controlled quantum phenomena along with specific guidance towards promising experimental directions for the field. A new text titled, Quantum Control Engineering, Taylor and Francis, will be co-authored by the PI and Professor R. Chakrabarti, Purdue University. The control of dynamical events at the atomic and molecular scale is at the heart of many areas of science. Building on the foundations of quantum mechanics and the introduction of the laser in the 1960's, an outstanding objective has been to achieve control at Angstrom length scales and ultrafast time scales. This field is motivated by the desire to manipulate and understand the fundamental dynamical processes as well as the prospects for a variety of applications. Addressing these goals reached a milestone through the introduction of engineering control concepts within quantum mechanics and the development of ultrafast laser pulse shaping tools. Hosts of emerging experiments demonstrate many of the basic principles and promise for the field. This research concerns the advanced development of theoretical concepts, tools and algorithms to fundamentally explore the control of quantum phenomena. These advances aim to provide the means to better exploit the laboratory control capabilities and extract the information generated from the experiments.