Triangle Quantum Computing Seminar Series: From Quantum State Tomography to Spin-Exchange Dynamics: Locally Controlled Rydberg Atom Arrays

ABSTRACT: Neutral atom arrays with Rydberg interactions are a promising platform for quantum technologies. The use of identical qubits allows scalability of the system and naturally enables global operations. However, certain tasks such as initialization into specific states require local control. In this talk, I will present two results that show how such local control enables us to probe and engineer many-body states. First, I will show how freely configurable ancillas allow quantum state tomography. By placing ancilla around the data qubits, each ancilla position serves as a distinct measurement basis, enabling tomography without full single-qubit operations. Next, I will demonstrate spin-exchange dynamics in an anisotropic Rydberg Heisenberg magnet. The wide tunability of our model, up to very large anisotropy together with long-range interactions, has allowed us to probe dynamics such as magnon quantum walk and the correlated motion of bound excitations. Together, these results illustrate how local control of Rydberg atom arrays opens new opportunities for engineering and probing many-body quantum dynamics. BIO: Kangheun Kim is currently a postdoctoral researcher at the Korea Research Institute of Standards and Science (KRISS). He received his Ph.D. in physics from KAIST in 2025 under the supervision of Prof. Jaewook Ahn, where he worked on neutral-atom quantum computing with Rydberg atom tweezer arrays. His research focuses on engineering and probing many-body quantum dynamics with programmable neutral-atom systems, including quantum state tomography, spin-exchange dynamics, and adiabatic quantum computations. --- The Duke Quantum Center, the IBM Quantum Innovation Center at NC State, and the UNC Kenan-Flagler's Rethinc. Labs are pleased to present the Fall 2025 Semester Triangle Quantum Computing Seminar series.