CUOS 12:30 PM Seminar: Prof. Yuki Kobayashi Coherent electronic phenomena in atoms, molecules, and two-dimensional materials

Light-energy conversion is ubiquitous in nature and technology. One of the big questions, that modern science faces is how we can harness the quantum nature of electrons in matters to transfer energy or store information in an efficient way beyond the thermodynamic limit. The key concept is “coherence,” which dictates whether different quantum states can interfere like waves to cause time-dependent modulation of the system. Making and reading coherence in real materials systems requires a broad bandwidth that matches with the electron-volt scaling of valence electronic states, now possible with ultrafast laser technology.
In this talk, I will present two exemplary systems from the coherence experiments. First, I will discuss how attosecond XUV pulses, combined with intense few-femtosecond pulses, can prepare and probe vibronic coherences in small molecules. Second, I will illustrate how ideas from atomic physics can be transposed to excitonic states in two-dimensional materials, enabling the realization of recollision physics in atomically thin semiconductors.
Lastly, I will outline my future research plan at the University of Michigan. This will concentrate on extending the use of attosecond spectroscopy to the photophysics of quantum materials.

Pizza will be served!