Towards the efficiency limit of visible LEDs

Thesis: S.M. in Electrical Engineering, Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 13-152).In this thesis, a thermophotonic method based on the heat-pump mechanism is proposed to potentially enhance the efficiency of visible light-emitting diodes (LEDs) for high-power operation. By leveraging this special mode of solid-state lighting by incoherent electroluminescent radiation and with the focus on gallium-nitride (GaN) technologies, we experimentally demonstrate a thermally enhanced blue LED operating in the low bias regime, and theoretically investigate the characteristics and criteria for efficiency visible lighting based on a thermodynamic study.by Jin Xue.S.M. in Electrical Engineerin