Ignacio Franco of the University of Rochester is supported by a CAREER award from the Chemical Theory, Models and Computational Methods program in the Chemistry Division to investigate the fundamental limits in the laser control of electrons and electronic properties in matter by exploiting quantum mechanical effects, an area of research known as quantum control. The focus is on lasers rather than more conventional means (e.g., an applied voltage, or changes in thermodynamic control variables) because lasers offer the possibility of change on an ultrafast timescale (on the order of a millionth of one billionth of a second). The Franco group investigates, for instance, the microscopic origin of the fastest existing method for the generation of currents, and the ability of lasers to turn insulating materials into transient metals. In addition to interest at a fundamental level, pushing the time limit in which electronic properties can be controlled has the potential to catalyze transformative progress in chemistry, spectroscopy, optoelectronic device design, communication through electrical signals, and any other science or technology based on electronic properties and their control. Professor Franco is impacting graduate education by redesigning the teaching of graduate level Quantum Mechanics in Chemistry through active learning pedagogies. With this project, he contributes to the development of a diverse, globally-engaged, U.S. science and engineering workforce by creating summer research opportunities for top international undergraduate students in Chemistry at the University of Rochester.
Specifically, the Franco group advances the capabilities of using high and intermediate intensity ultrafast laser pulses to manipulate electronic properties and dynamics in nanoscale matter. The vision of the group is to establish structure-function relations that apply to matter driven far from equilibrium by laser fields, and to push the limit in which control of electrons is exerted. A fundamental limit that has historically hindered progress in the quantum control of electrons is the deleterious effects on the control introduced by ultrafast electronic decoherence processes arising from electron-nuclear interactions. To overcome this limit, Professor Franco and his research group: (i) Identify, model, and quantify basic mechanisms for electronic coherence loss, as a necessary step in the design of laser control scenarios that either avoid or take advantage of the decoherence. (ii) Develop novel routes for laser control of electrons based on the Dynamic Stark Effect induced by non-resonant laser fields of intermediate intensity (non-perturbative but non-ionizing) that are robust to decoherence. Together, these developments catalyze the design of novel control experiments, ultrafast opto-electronic technologies, and a new class of dynamic electronic materials with effective laser-induced properties tunable on a femtosecond timescale. This project incorporates an integrated research and educational plan that provides students with a unique opportunity for interdisciplinary training and collaborative work at the interface between Chemistry, Physics, Nanoscience and Optics. The work impacts graduate education, through a proposed redesign of the teaching of graduate level Quantum Mechanics in Chemistry by incorporating active learning pedagogies, such as flipped classrooms and peer learning problem solving sessions.
