Jingyun Fan is a physicist affiliated with the National Institute of Standards and Technology and the Joint Quantum Institute of University of Maryland. He contributed to the early development of fiber-based photonic entanglement, which is now a standard tool as an alternative to spontaneous parametric down-conversion for quantum information processing tasks. His contributions to spontaneous parametric down-conversion include achieving a collection efficiency for a two-photon pair source that for the first time exceeds the threshold needed for a loop-hole free test of Bell’s inequality. His recent work in the field of quantum measurement science involves the demonstration of a number of strategically designed quantum measurement protocols that bridge the gap between quantum communication and coherent optical communication for the first time. His most recent work explores the interaction of light in complex photonic systems as a way to simulate a range of physical phenomena not easily accessible through other means.