The study of how light interacts with matter has been ongoing for centuries. In the 1920s, quantum mechanics revolutionized our understanding of this field. Since then, countless fascinating effects have been discovered that rely on the quantum nature of matter. One such discovery led to the invention of the laser, which in turn has enabled us to study how matter behaves under intense laser pulses. In strong laser light, matter can behave in “strange ways”: For example, it can absorb two or more particles of light (photons) at once. This is not purely academic! Most green lasers work through this process.

In previous decades, laser pulse sources have become more powerful, and scientists have gained impressive control over the pulse properties. This has made new regimes of light-matter interaction accessible. In my research, I explore such new regimes and try to describe the effects that happen in them. I am especially interested in the regime in which light and matter become strongly coupled. In this regime, the electron’s energy can oscillate between two values as it periodically absorbs and re-emits a light particle. This process is quite fundamental in light-matter interaction and is known as Rabi oscillations. Again, it is not purely academic, being essential to Nuclear Magnetic Resonance Imaging in medicine (MRI) and analytical chemistry (NMR).

I study such phenomena using both simulations and simplified models.  For the simulations, I use computer code that solves the underlying complicated equation, known as the time-dependent Schrödinger equation (TDSE). The model systems are build by taking the TDSE and enforcing simplifying assumptions and approximations that are tailored to the specific system of interest. In the best case, this transforms the TDSE into an equation whose solution can be written out with just pen and paper.