Jeff Moses joined the faculty in the School of Applied and Engineering Physics at Cornell University in 2014. Before that, he worked at MIT as a research scientist and principal investigator of federally sponsored research programs in ultrafast nonlinear optics, attosecond sources and physics, and molecular and chemical physics. Moses received his Ph.D. from Cornell in 2007, and his B.Sc. from Yale in 2001, with both degrees in applied physics. He is currently leading programs funded by the National Science Foundation, the Department of Energy, and the Office of Naval Research.
Jeff Moses’ research group focuses on capturing “ultrafast phenomena” in real time (i.e., capturing events so brief as to be barely detectable by state-of-the-art technology), and on developing the light-pulse and time-resolved spectroscopic technologies for doing so. We focus on using laser pulses analogously to strobe lights, in order to view brief moments during the coordinated motions of electrons and coupled particles. Current systems of interest include light-activated biophysical systems, such as DNA and the human vision response, and highly correlated materials such as perovskite crystals that can be modified with light on ultrafast timescales.
We are also developing concepts for producing extremely broadband light sources, for efficiently amplifying intense pulses of light, for changing the color of quantum light, and for the establishment of a stroboscope emitting femtosecond pulses covering the electromagnetic spectrum from THz to extreme ultraviolet frequencies. Our techniques fall under the category of ultrafast nonlinear spectroscopy, and within the purview of the broad field of nonlinear optics.
The shortest laser pulses today, lasting only femtoseconds or attoseconds (millionths or billionths of billionths of seconds) are faster than electronic motion, and can be used to capture the ultrafast events that fundamentally change electronic behavior. Several related questions motivate our work: How fast are the fastest events that serve an important function in the behavior of a material? Can we see them happen? Can we determine the conditions under which these ultrafast motions are important and engineer new systems that take advantage of their useful properties?
By endeavoring to connect ultrafast phenomena to real-timescale systems, our work naturally seeks to connect atomic level dynamics to complex chemical and biological processes, and, likewise, to connect quantum mechanical behaviors to phenomena traditionally expected to act classically. The dynamics of photo-excitable systems are one of our main targets, as these are important in processes as widespread as DNA photo-damage and the initial steps of charge separation in photovoltaics. Moreover, by learning how these mechanisms work, we hope to gain insights into natural behaviors that can be used to engineer better technologies.
