Out-of-Equilibrium Dynamics of Quantum Systems

Science illustration.

Out-of-equilibrium kinetics and dynamics of coupling between charges, spins and atoms are often exceedingly difficult to capture and understand because of insufficient investigative tools in both experiment and theory.

The JILA PFC has taken on the challenge of creating tools to identify, observe, and control ultrafast electronic dynamics and chemical reaction pathways in real time. Specifically, our goals are to observe coupled dynamics in different forms of matter, mainly solids and molecules, as well as the formation and transformation of constituents in reactions on unprecedented time scales, spanning a range from 10-18 s to 10-6 s.

To accomplish these goals, we use frontier laser sources that produce ultrashort pulses spanning from
 the infrared to the soft X-ray region. We also synthesize cold molecules and probe them with emerging frequency comb technology. Key ingredients in this research are new high-harmonic light sources developed at JILA. These light sources that can produce isolated attosecond pulses or pulse trains, now with controllable polarization as well as spectral and temporal structure. Moreover, new measurement techniques are opening up new scientific capabilities, such as the ability to combine high resolution in energy and time, that provide new windows into electron-electron interactions on sub-femtosecond time scales. The JILA PFC has also developed the expertise to control quantum states of simple molecules, which takes advantage of advances in both precision measurement and molecular science. The combination of cold molecules, traps, and frequency combs enables novel tools for precise control and quantitative tracking of molecular systems at a quantum-state resolved level.

Specific projects within this major activity

  • Understanding reaction pathways and transient intermediates, including photon initiated chemistry in cold environments, observing and controlling ion-molecule reactions in cold environments, and preparing molecules with precise control over quantum states
  • Probing and time-resolving electron dynamics and correlation, including attosecond measurement science, capturing electron dynamics in nanoparticles probed with advanced spectroscopy, and capturing and characterizing attosecond electron-electron interactions in materials