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The Photonics at Thermodynamic Limits Energy Frontier Research Center (PTL-EFRC) strives to achieve photonic operations at thermodynamic limits by controlling the flow of photons, electrons, and phonons in atomically-architected materials, and thereby enable entirely new energy conversion systems.

New Photonic Thermodynamic Cycles

Thermodynamic cycles enable optimized performance of nearly every energy conversion device that underpins advanced economies. While most thermodynamic cycles rely on a classical fluid, photons can also be used to drive thermodynamic cycles. Such photon-based Carnot cycles offer remarkable opportunities for energy conversion, including all-optical energy-storage, optical refrigeration, optical rectification, lensless concentration, excited-state photocatalysis, and beyond von-Neumann information architectures.

Realizing photonic thermodynamic cycles requires new optical materials design, synthesis and characterization so that photonic operations - such as absorption, emission, and reflection – can be performed with the highest possible efficiency.

Team of Leading Researchers

To pioneer photonic thermodynamic cycles, we have assembled an integrated, collaborative team of 12 faculty spanning 5 departments at Stanford, Berkeley, Caltech, Harvard, and UIUC. The PTL-EFRC is directed by Prof. J. A. Dionne and centered at its lead institution, Stanford University. Members of our EFRC contribute leading expertise in photonics, materials synthesis, theory and measurement science.

This bold mission demands a multi-faceted EFRC-level effort where theory provides insights to guide materials synthesis and energy conversion systems that are in turn validated by state-of-the-art characterization at the nanometer to atomic scale with ultrafast time resolution.

Expected Outcomes

Our long-term goal is to design photonic conversion systems for energy and information that operate at thermodynamic limits, and to share our research with technologists, policymakers and the public to maximize the societal impact of our EFRC. Our expected outcomes of the integrated RG efforts include:

  • New forms of matter, suggested by theoretical insights and synthesized with atomic precision, that achieve unprecedented levels of optical efficiency
  • New foundational understanding of the thermodynamic and quantum limits to excited state generation and lifetime in atomically-architected optical materials, informed by theory and ultrafast/nanoscale characterization methods
  • Development of new theoretical methods to describe optically excited states and processes
  • Development of new characterization methods to determine optical efficiency and observe excited state relaxation processes with unprecedented detail and resolution
  • A set of photonic thermodynamic cycles that use light as the working fluid and perform work with an efficiency approaching the Carnot efficiency.
Radiative Optical Efficiency