CM-AMO Seminar | Tailoring Rydberg interactions for expanding quantum capabilities

Rydberg atoms provide a uniquely versatile platform for engineering strong, tunable interactions in otherwise weakly interacting neutral-atom systems. They couple strongly to each other and to external fields. The former enables controllable atom-atom, atom-photon and even photon-photon interactions, while the latter promises exceptionally sensitive and broadband microwave (MW) and radio frequency (RF) sensing capabilities. Typically, the Rydberg-Rydberg interactions are leveraged as a blockade mechanism. In contrast, we explore the antiblockade regime in atom arrays, where interactions facilitate rather than suppress excitation. I will present our numerical studies demonstrating directional quantum information and entanglement transfer [1], as well as robust avalanche amplification for weak signal detection [2]. For atom-field coupling, I will present our experimental work expanding MW sensing capabilities with cold atomic ensembles. First, we demonstrate 3D field characterization via multi-parameter extraction, which holds potential as a testbed for machine-learning-enhanced measurement protocols and has broad implications for information extraction from complex measurements. Second, we address the intersection of atom-atom and atom-field interactions by investigating the role of nonlinear atomic interactions in probing external fields [3]. Together, these studies show how tailoring Rydberg interactions expands the accessible measurement and dynamical capabilities of cold-atom platforms.

References:
[1] Yupeng Wang, Junjie Wang, Aishik Panja, Xinghan Wang, Qi-Yu Liang, “Directional Transport in Rydberg Atom Arrays via Kinetic Constraints and Temporal Modulation”, Phys. Rev. Research 7, L022035 (2025)
[2] Xinghan Wang, Yupeng Wang, Qi-Yu Liang, “Robust Rydberg facilitation via rapid adiabatic passage”, Phys. Rev. Research 8, 013154 (2026)
[3] Xinghan Wang, Yupeng Wang, Aishik Panja, Qi-Yu Liang, "Nonlinear optical spectra from Rydberg-mediated photon photon interactions", arXiv:2602.11563 (2026)