This is what fun looks like for a particular set of theoretical chemists driven to solve extremely difficult problems: Deciding whether the electromagnetic fields in molecular polaritons should be treated classically or quantum mechanically.
This is what fun looks like for a particular set of theoretical chemists driven to solve extremely difficult problems: Deciding whether the electromagnetic fields in molecular polaritons should be treated classically or quantum mechanically.
Graduate student Millan Welman of the Hammes-Schiffer Group is first author on a new paper that presents a hierarchy of first principles simulations of the dynamics of molecular polaritons. The research is published in the Journal of Chemical Theory and Computation.
Originally 67 pages long, the paper is dense with von Neumann equations and power spectra. It explores dynamics on both electronic and vibrational energy scales. It makes use of time-dependent density functional theory (DFT) in both its conventional and nuclear-electronic orbital (NEO) forms. It spans semiclassical, mean-field-quantum, and full-quantum approaches to simulate polariton dynamics.
Welman had fun putting it together.
„There is data that exists from the experimental world which suggests that you can modify the rates of chemical reactions by performing them in an optical cavity under strong interactions with an electromagnetic field“, said Welman. „It’s a wonderful, fun problem. I loved it. Because if those experiments are actually onto something, that would be pretty transformative.“
Polaritons are roughly defined as quasiparticles generated by strong light–matter interactions. They are complicated systems we don’t fully comprehend, but they could help advance our understanding of how to control molecular behavior using light.
The paper provides a conceptual framework through which experimentalists might look for unique behaviors by treating light (i.e. the electromagnetic wave) quantum-mechanically that are not apparent by treating it classically. The signature of that difference is any evidence of quantum entanglement between the photons and the molecules.
