
Contact Information
355D Noyes Lab
Mailing address:
600 S. Mathews Avenue, Box 42-1
Urbana, IL 61801
Research Areas
Additional Campus Affiliations
Professor, Physics
Affiliate, Beckman Institute for Advanced Science and Technology
Affiliate, Computational Science and Engineering Program
Affiliate, Illinois Quantum Information and Technology Center
Biography
Professor Nancy Makri received her B.S. from the University of Athens in 1985 and her Ph.D. from the University of California at Berkeley in 1989. She spent two years as a Junior Fellow at Harvard before joining the faculty at Illinois in the spring of 1992. Her research interests are in theoretical quantum dynamics.
Research Interests
theoretical quantum dynamics of large molecules and condensed phase systems, with applications to relaxation, charge transfer reactions, and quantum control of nanostructures
Research Description
We strive to advance theoretical understanding of quantum mechanical processes in large molecules and the condensed phase. Full solution of the Schrödinger equation is feasible only for small molecules, as the required numerical effort increases exponentially with the number of particles. We develop new theoretical approaches and simulation methods based on Feynman’s path integral formulation of quantum dynamics and its semiclassical limit.
Methodology. The path integral representation avoids storage of multidimensional wave functions at the cost of introducing auxiliary integration variables at each time step. Evaluating the resulting multidimensional integrals presents a challenge: the number of paths grows exponentially with time, while importance sampling fails due to phase cancellation.
We developed the first rigorous methodology for following the dynamics of a quantum particle interacting with a polyatomic medium. A path integral represents the subsystem of interest, while the collective effects of the environment are evaluated in the semiclassical approximation using trajectories in combined forward-backward time to alleviate the phase cancellation problem. Through dephasing effects, the medium helps shorten the range of temporal correlations, allowing an exact decomposition of the path sum into an iterative scheme that circumvents the need for global summation over astronomical numbers of paths. The method allows a faithful description of all aspects of quantum mechanical processes in condensed phase environments and, if the environment consists of harmonic phonon modes, yields the exact quantum mechanical result.
Reaction Rates. We have performed path integral calculations to benchmark adiabatic and nonadiabatic reaction rates in generic dissipative environments and to explore the interplay between coherence and dissipation at low temperatures. Our simulation of hydrogen diffusion in silicon identified important tunneling contributions and an inverse isotope effect.
Photosynthesis. Our path integral simulations helped resolve a long-standing controversy concerning the primary charge separation mechanism. Further, we have been exploring the energy transfer process in light-harvesting complexes using the path integral representation of quantum statistical mechanics.
Quantum Control. We are investigating the possibility of using coherent light to manipulate exciton tunneling and transport in nanostructures. We have identified novel mechanisms for sustaining charge localization or inducing coherent oscillations in semiconductor double-quantum wells.
Awards and Honors
ACS Physical Chemistry Division Award in Theoretical Chemistry, 2021
School of Chemical Sciences Teaching Award, University of Illinois, 2020
The 2019 Löwdin Lecturer, Uppsala University, Sweden
Member, International Academy of Quantum Molecular Science, 2010
Fellow, American Physical Society, 2001
Bodossaki Academic Prize in Physical Sciences, 2000
University Scholar, 1999
Agnes Fay Morgan Research Award, 1999
Fellow, American Association for the Advancement of Science, 1998
Camille Dreyfus Teacher-Scholar Award, 1997
Annual Medal of the International Academy of Quantum Molecular Science, 1995
Sloan Research Fellowship, 1994
Cottrell Scholar Award, 1994
Beckman Young Investigator Award, 1993
National Science Foundation Young Investigator Award, 1993
Packard Fellowship for Science and Engineering, 1993
Recent Publications
Bose, A., & Makri, N. (2020). All-Mode Quantum-Classical Path Integral Simulation of Bacteriochlorophyll Dimer Exciton-Vibration Dynamics. Journal of Physical Chemistry B, 124(24), 5028-5038. https://doi.org/10.1021/acs.jpcb.0c03032
Chatterjee, S., & Makri, N. (2020). Recovery of Purity in Dissipative Tunneling Dynamics. Journal of Physical Chemistry Letters, 11(20), 8592-8596. https://doi.org/10.1021/acs.jpclett.0c02513
Kundu, S., & Makri, N. (Accepted/In press). Efficient matrix factorisation of the modular path integral for extended systems. Molecular Physics. https://doi.org/10.1080/00268976.2020.1797200
Kundu, S., & Makri, N. (2020). Modular path integral for finite-temperature dynamics of extended systems with intramolecular vibrations. Journal of Chemical Physics, 153(4), [044124]. https://doi.org/10.1063/5.0014838
Kundu, S., & Makri, N. (2020). Real-Time Path Integral Simulation of Exciton-Vibration Dynamics in Light-Harvesting Bacteriochlorophyll Aggregates. Journal of Physical Chemistry Letters, 11(20), 8783-8789. https://doi.org/10.1021/acs.jpclett.0c02760