中文版
Events

Extraordinary Radiative Heat Transfer at the Nanoscale

Release time:April 22, 2017 / Siying He

Topic:

Extraordinary Radiative Heat Transfer at the Nanoscale      

Speaker:Postdoctor Bai Song, MIT.      

Date:April 24th (Monday)14:30-16:30 PM      

Venue: C708, new main building  

 

Abstract:      

Radiative heat transfer between objects separated by nanometer-sized gaps is of considerable interest for a variety of novel applications, including energy conversion, thermal logic, lithography, data storage, and scanning thermal microscopy. Although thermal radiation over macroscopic distances is well understood in terms of Planck’s law and the Stefan-Boltzmann law, radiative heat transfer at the nanoscale remains largely unexplored. In this talk I will address some of the most important questions in the field of nanoscale thermal radiation: 1) Can existing theories accurately describe radiative heat transfer in gaps as small as a few nanometers in size? 2) Can nanometer-thin films effectively interact with nanoscale radiation characterized by wavelengths in the micrometer range? 3) Can radiative thermal conductances in nanoscale gaps exceed those between blackbodies by a few orders of magnitude? To answer these challenging questions I built novel experimental platforms featuring nanometer-precise positioning mechanisms in conjunction with novel microdevices and scanning probes. Further, I performed state-of-the-art calculations and analysis to compare theoretical predictions with experimental observations. I will demonstrate that: 1) Current nanoscale radiation theories can adequately describe radiative heat transfer down to 2 nm gaps. 2) Nanometer-thin films can enhance radiative heat transfer in nanometer gaps as effectively as bulk materials. 3) Radiative thermal conductances can exceed the blackbody limit by about 100 times. Finally, I will outline how these advances will enable important and essential investigations of both nanoscale radiative heat transport and its application to energy conversion technologies such as thermophotovoltaics.

 

Brief Intro of the Speaker:      

Dr. Bai Song (宋柏) received his Ph.D. in Mechanical Engineering in 2015 at the University of Michigan, Ann Arbor, where he was honored with the Distinguished Dissertation Award (university wide, ≤10 awardees annually). He obtained his M.S. and B.E. degrees in the School of Aerospace at Tsinghua University. Under the mentorship of Prof. Zeng-Yuan Guo, he was a recipient of the Distinguished Master Thesis Award. He is currently a postdoctoral associate at MIT, working with Prof. Gang Chen in the Mechanical Engineering Department. He is an author of many publications including in Nature and Nature Nanotechnology. His primary research interest is to understand energy transport, conversion and storage mediated by photons, phonons and electrons, especially at extremely small spatial and time scales. He further aims to leverage such knowledge to design novel energy materials and devices, and to develop thermal management strategies for next-generation electronic and optoelectronic systems.      

 

   School of automation science and electrical engineering