Nico Felicien Declercq (Kortrijk (Belgium), 27 December 1975) is a physicist and mechanical engineer. He is a professor with the Georgia Institute of Technology in Atlanta and Georgia Tech Lorraine in France. He is specialized in ultrasonic nondestructive evaluation of materials, propagation of ultrasonic waves in highly complex materials, in acoustics, in theoretical and experimental linear and nonlinear ultrasonics, acousto-optics, Medical Physics and Acoustic Microscopy. He has investigated the acoustics of Chichen Itza and Epidaurus.