Stefan Ostermann, Postdoctoral Fellow at Harvard University, will be presenting "Advancing the Quantum Frontier: The Interplay of Atoms, Photons, and Programmable Quantum Simulation" as part of the Quantum Research Institute's winter seminar series from 2:00 - 3:00 pm in Room 340 at West Hall. A Zoom option is also provided.

Seminar Description:

Over the past few decades, atomic-, molecular-, and optical (AMO) physics has seen remarkable advances in manipulating individual quantum systems, such as atoms and photons. State-of-the-art techniques can precisely trap, arrange, and manipulate arrays of hundreds of individual atoms with light. This significantly advances our ability to investigate complex many-body quantum effects in well-controlled environments.

In this talk, I will present our recent work that utilizes atom arrays to unveil and study intriguing quantum phenomena. The first part will focus on the dissipative many-body dynamics that arise when atoms within these arrays interact via photon-mediated long-range dipole-dipole interactions. This gives rise to phenomena like super- and subradiance, where photon emission from the array is either significantly enhanced or diminished due to collective effects. I will first illustrate the dynamics in cases where interactions within the array are mediated by just a single photon, shedding light on key mechanisms for quantum transport in geometries inspired by biological compounds. Then, I will present our results in the more complex multi-excitation regime, elucidating some core characteristics of superradiance for large system sizes.

I will then shift focus to how atom arrays can be used as programmable quantum simulators, when atoms are excited to strongly interacting Rydberg states. I will introduce a toolbox for simulating quantum chemistry problems, using hardware-optimized control sequences to accurately realize the time evolution of complex spin Hamiltonians. Additionally, I will discuss a method for extracting chemically relevant data from snapshot measurements taken at different times.