Jan 23, 2020 3:45 pm - Nielsen Hall 170 (Neal F. Lane Auditorium) - Colloquium
Richard Schmidt - Max Planck Institute for Quantum Optics, Garching
Exploring polarons: From cold atoms to two-dimensional materials

When an impurity is immersed into an environment, it changes its properties due to its interaction with the surrounding medium. The impurity is dressed by excitations in the bath and, depending on the nature of the environment, new collective states of matter are formed. Often these states share much similarity with the original impurity and quasiparticles, called polarons, are formed.  In another extreme, new quantum states are realized that are completely orthogonal to the original state of the system. In this colloquium, I will present recent experimental and theoretical progress on studying a variety of polaronic phenomena encountered in ultracold atomic, quantum optical and solid state systems. In particular I will show how atomic quantum gases can be successfully employed as a platform to simulate the physics of novel two-dimensional semiconductor materials. In the second part of the colloquium I will focus exploring polaronic effects in Rydberg systems. Here the interaction between the Rydberg atom and their surrounding atomic gas gives rise to a new polaronic dressing mechanisms, where molecules of gigantic size dress the Rydberg impurity, leading to the formation of Rydberg superpolarons. I will discuss the theory describing the formation of Rydberg superpolarons, their recent observation and relevance for our understanding of the decoherence dynamics of quantum optics experiments using Rydberg atoms.