Dr. Bennett is recognized for a series of theoretical breakthroughs in the fundamental understanding and design of superconducting transition-edge sensors (TESs). He developed a new, two-fluid model for the resistive transition in the sensors; explained their resistance mechanism; and resolved a fifteen-year mystery of unexplained electrical noise. Using these insights, NIST dramatically improved the speed and spectral resolution of TES sensors in a unique x-ray tomography tool for microelectronic circuit analysis and at national synchrotron beamlines for materials spectroscopy.