My research group and I focus on statistical mechanics at the molecular level. We are particularly interested in the foundations of nonequilibrium thermodynamics, the application of statistical mechanics to problems of biophysical interest, the analysis of artificial molecular machines, and the development of efficient numerical schemes for estimating thermodynamic properties of complex systems.
Major Recognitions and Honors
Significant Professional Service and Activities
Five undergraduates and one graduate student mentored as part of summer programs at the University of Washington and Los Alamos. Four postdoctoral associates,six graduate students, and three undergraduates at U. of Md. (since 2006).
n the Jarzynski group, we carry out research related to the thermodynamics of microscopic systems. We develop theoretical tools for understanding nonequilibrium behavior, and computational methods for estimating thermodynamic properties, and we construct and analyze simple models that provide insight into complex phenomena. The following descriptions provide a flavor of the research that goes on in our group.
Nonequilibrium work and fluctuation relations.
While the laws of thermodynamics were developed nearly two centuries ago to describe macroscopic systems such as steam engines, recently there has been considerable interest and exciting progress in understanding how these laws apply to nanoscale systems, especially in situations far from thermal equilibrium. At microscopic length scales, random fluctuations due to thermal noise are prevalent, and together with colleagues around the world we investigate the universal laws that govern these fluctuations. For a recent review of some of this progress, click here.1
Numerical simulations are widely used to compute thermodynamic properties of complex systems, and the estimation of free energy differences is particularly challenging and important. While free energy estimation has traditionally relied on equilibrium simulations, we develop methods that provide the same information using nonequilibrium simulations. Recently, we have shown how the use of artificial flow fields in such simulations can greatly boost their efficiency2, and we have developed a nonequilibrium extension of the widely used replica exchange method.3
Principles for the design of artificial molecular machines.
Life would not be possible without the host of biomolecular machines that perform tasks such as pumping ions across cell membranes, copying the genetic code, and causing muscles to contract. Inspired in part by Nature’s example, researchers in numerous laboratories are synthesizing molecular rotors, single-molecule “walkers”, and other building blocks of artificial nanoscale machines. In our group we try to discover general principles underlying the behavior and the control of such systems.4
1. C. Jarzynski, “Equalities and inequalities: Irreversibility and the second law of thermodynamics at the nanoscale”, Annu. Rev. Condens. Matter Phys. 2:329-51 (2011).
2. S. Vaikuntanathan and C. Jarzynski, “Escorted free energy simulations: improving convergence by reducing dissipation”, Phys. Rev. Lett. 100, 190601 (2008).
3. A. J. Ballard and C. Jarzynski, “Replica exchange with nonequilibrium switches”, to appear in Proc. Natl. Acad. Sci. (USA) (2009).
4. S. Rahav, J. Horowitz and C. Jarzynski, “Directed flow in non-adiabatic stochastic pumps”, Phys. Rev. Lett. 101, 140602 (2008).