Modern quantum technologies depend on our ability to understand, predict, and ultimately engineer interactions between electrons, excitons, spins, and photons. In this colloquium, I will describe a method of turning quantum materials into programmable quantum systems. I will first briefly discuss how many-body GW–Bethe–Salpeter and Kadanoff–Baym approaches provide a predictive framework for the linear and nonlinear optical response of two-dimensional semiconductors, including excitonic effects, harmonic generation, and design rules for enhanced nonlinear response in layered materials. I will then focus on recent work showing that a gate-tunable conductor–dielectric–conductor heterostructure can provide universal tuning of quantum electrodynamic interactions: the same platform allows interactions to be switched from familiar power-law behavior to exponential screening and even logarithmic antiscreening, with direct implications for reconfigurable Coulomb, dipolar, van der Waals/Casimir–Polder, and spin–spin interactions.

 Bio:
Michael N. Leuenberger is Professor of Theoretical Condensed Matter Physics at the University of Central Florida, with appointments in the NanoScience Technology Center and Department of Physics. He is also a Visiting Scientist at MIT. He received his Ph.D. in theoretical condensed matter physics from the University of Basel, Switzerland, under Daniel Loss, and subsequently held postdoctoral positions at the University of Iowa with Michael Flatté and at UC San Diego with Lu Sham. His research spans quantum information science, nonlinear optics, many-body theory of quantum materials, and multiscale modeling of quantum devices. He has led or co-led research supported by AFOSR, ARO, DARPA, NSF, and ONR, and his recent work includes predictive many-body theories of nonlinear optical response in 2D materials, excitonic quantum matter in breathing-kagome materials, and programmable quantum electrodynamic interactions in van der Waals heterostructures.