Exploring Many-Body Interaction and Correlation in Atoms
for Quantum Information Science

Future scalable and reliable universal quantum computers can be more superior than classical computers for solving certain problems. To fully harness the power of quantum mechanics, the quantum computing platform must be a many-body system with interacting or coupled quantum entities (qubits). For example, entangling multiple qubits requires coupling and coherence. The behavior of an assemble of interacting particles cannot be understood by a simple extrapolation of the microscopic lawas of single particles. Instead, entirely new properties can appear at each level of complexity, as pointed out by P.W. Anderson in 1972. Experimentally understanding new principles and laws in many-body systems is essential for both fundamental many-body physics and ultimately providing practical solutions for future scalable and reliable quantum computers. 

In this talk, I will present our recent studies of many-body interaction and correlation in potassiurm and rubidium atoms by using a novel ultrafast spectroscopic technique, known as optical two-dimensional coherent spectroscopy. This technique provides an extremely sensitive and background-free detection of coupling and coherence in multi-atom Dicke states. Our results revealed that the effective range of dipole-dipole interaction can extend to at least tens of micrometers. We have also observed multi-atom Dicke states with a scalable and deterministic number of atoms from two to eight atoms, providing the prerequisite for generating entangled states of up to eight atoms. Our ongoing work is to extend the study into an array of rubidium atoms trapped in optical tweezers and an array of color centers in solids.   

Speaker bio: Dr. Hebin Li is currently an associate professor in the Department of Physics at Florida Interanational University (FIU). He received his BS in physics from Wuhan University and his PhD in physics from Texas A&M University in 2010. After three-years of postdoctoral study at JILA, a joint institute of University of Colorado at Boulder and National Institute of Standards and Technology, Dr. Li joined FIU as an assistant professor in 2013 and was later promoted to an associate professor in 2019. During his tenure at FIU, Dr. Li has established a successful research program with a well-equiped ultrafast spectroscopy and quantum optics lab. His research interest focuses on experimental study of many-body quantum systems and their potential applications in quantum information science. Dr. Li is a Senior Member of Optica (formerly OSA). He has won awards including William R. Jones Oustanding Mentor Award (2021), Army Research Lab Summer Faculty (2020), FIU Top Scholar (2020), and FIU CASE Research Award (2017, 2020).