 Steven G. Johnson

A researcher and teacher whose work connects electromagnetic waves with mathematical and computational methods. His MIT course treats optical structures whose dimensions are comparable to a wavelength, using eigenvalue problems and Bloch's theorem to explain photonic crystals. Periodic changes in a material can exclude a range of optical frequencies, while a defect can localize light; this gives a physical reason to study both periodic structures and their imperfections.^[ref]

Steven G. Johnson is a prominent physicist and professor known for his work in the fields of applied physics, mathematics, and optics. He is a faculty member at the Massachusetts Institute of Technology (MIT) and has made significant contributions to the areas of photonics, wave phenomena, and computational methods in physics.