Heat is a by-product of everything from semiconductor chips to industrial processes, and roughly ~60% of generated power is ultimately rejected as waste heat. The rise of AI hardware and data centers only amplifies this energy-management challenge. We develop thermophotovoltaic (TPV) solutions that convert thermal radiation from a hot source directly into electricity via the photovoltaic effect. Our work advances near-field TPV, plasmonics, and optoelectronics to push efficiency and power density, supported by custom high-temperature instrumentation, precision characterization, and nano-positioning tools. We study these systems at both fundamental and applied levels to enable compact generators and practical waste-heat recovery. 

Any two bodies at different temperatures exchange energy through thermal radiation. In the far field, this heat transfer is described by Planck’s law, which sets a blackbody limit on radiative exchange. When the characteristic dimensions are below the thermal wavelength, this framework breaks down: new, nanoscale light–matter interactions emerge that enable control of energy transport. We study two broad questions: (1) how thermal radiation behaves across nanometer gaps—near-field radiative heat transfer (NFRHT)—and (2) how radiation is modified between nanometer-sized objects. By understanding and controlling radiative heat transfer at the nanoscale, we aim to advance thermal management in AI hardware, photonic devices, and quantum systems. 

Calorimetry—measurement of heat fluxes—has enabled advances across many fields. In recent decades, driven by nanotechnology, measurement techniques have pushed calorimetric resolution down to the femtowatt (fW) scale. In this research direction, we apply and extend these advances for biological systems. In the past, our tools enabled studies on metabolism in systems ranging from C. elegans to Drosophila brains. This capability opens avenues for probing disease mechanisms, diagnosing metabolic disorders, and supporting new therapeutic development. 

Phase change from liquid to vapor underpins boiling, HVAC, desalination, and climate modeling. Recent nanoscale materials engineering and advances in heat and mass transfer have renewed interest in phase-change systems for solar desalination, atmospheric water harvesting, and radiative cooling. We aim to develop low-cost systems to address water scarcity and enable passive energy savings.

Electronic devices sparked the digital revolution by controlling electron flow with diodes and transistors. Analogously, heat can be manipulated with thermal logic devices that route, rectify, and switch energy. There is growing scientific interest in realizing thermal diodes (one-way heat flow) and thermal transistors (gated/switchable heat flow). We design and test radiative thermal diodes and photonic thermal transistors, enhancing rectification, gain, and speed. These efforts aim to enable thermal logic for robust thermal management in extreme environments.