Photons as Energy and Fuel: Harnessing Nanoscale Light-Matter Interactions in Terrestrial and Space Domains.
Ognjen Ilic, Postdoctoral Scholar, Department of Applied Physics and Materials Sciences, California Institute of Technology
The diverse range of available thermodynamic resources—from the Sun at 6,000 degrees to cold space at 3 degrees—offers great potential for energy and environmental applications. To harness these resources, the ability to control radiative energy processes is of vital importance. In the first part of my talk, I will discuss how nanoscale photonic structures and two-dimensional material platforms can manipulate thermal electromagnetic fields in unprecedented ways. I will present work on tailoring thermal emission by photonic elements that enable light recycling, which could lead to high efficiency lighting and heat-to-electricity energy harvesting. I will also show how nano-architected two-dimensional materials can challenge conventional thermal radiation, from radiative energy exchange that overcomes the Planck’s blackbody limit, to active manipulation of thermal signatures.In the second part of my talk, I will discuss how optical manipulation of objects with engineered nanostructure can open up frontiers in opto-mechanics, from guided actuation at the nanoscale to new levitation and propulsion paradigms. I will show how macroscopic—mm, cm, or even meter-scale—objects could be stably manipulated at arbitrary distances by embedding nanoscale elements that control the anisotropy of light scattering along the object surface. Finally, I will outline a vision for harnessing the momentum of light for space exploration. With photons as fuel, light-driven spacecraft could reach ultra-high, even relativistic velocities needed for deep space and interstellar spaceflight, including Breakthrough Starshot, an ambitious mission to send a probe to Alpha Centauri. Leveraging the progress in materials, fabrication, and nanophotonic design, we can now begin to address such visionary opto-mechanical applications, on Earth and in space.
Ognjen Ilic is currently a postdoctoral scholar in the Department of Applied Physics and Materials Science at Caltech. Prior to coming to Caltech, he received his Ph.D. in physics from MIT, and completed his A.B. in physics and mathematics at Harvard University. His research themes encompass light-matter interactions in nanoscale structures and low-dimensional materials. He is particularly interested in radiative energy transport, renewable energy and efficient energy harvesting, opto-mechanics and light-driven dynamics, and algorithmic design and optimization of nano-structured materials. His work has been featured in various media outlets including Scientific American, The Economist, and Popular Science. More details can be found at https://www.its.caltech.edu/~ilic