第426回GMSI公開セミナー／第171回WINGSセミナー

Engineered Nanostructured Materials for Advanced
Thermal Management, Rectification, and Encryption

Professor Sheng Shen

Department of Mechanical Engineering
Department of Electrical and Computer Engineering (Courtesy)
Department of Materials Science and Engineering (Courtesy)
Carnegie Mellon University

Date： Monday, July 22, 2024 10:30-11:30

Venue： Faculty of Engineering Bldg. 2, Room 31A
Abstract: In this talk, I will give three examples about utilizing specially engineered nanostructured
materials to develop advanced thermal components. First, I will introduce new types of nanostructuredthermal interface materials that can thermally bridge the interfaces with ultra-low thermal resistance andmechanical compliance. Compared with the state-of-the-art thermal interface materials, thenanostructured thermal interface materials exhibit a thermal resistance as small as about 0.5 mm2K/W,
polymer-like compliance, and exceptional long-term reliability with >1,000 thermal cycles over a wide
temperature range. With the significantly enhanced heat transfer and reliability, these nanostructured
thermal interface materials hold great promise for enhancing the thermal management of energy-dense
devices and systems, contributing to future energy efficiency and sustainability. Second, I will report anultra-high-contrast and reversible nanoscale thermal switch based on the structural phase transition in
crystalline polyethylene nanofibers, which enables a ~ 10X thermal switching ratio between the on-state(high) and the off-state (low) thermal conductance values. The observed high switching ratio exceeds by
far any reported experimental values for solid-solid phase transition, solid-liquid phase transition anddesiccation-hydration of materials. By fabricating a heterogeneous “irradiated-crystalline nanofiberjunction” using an electron beam, we also demonstrate a high-performance solid-state nanoscale thermal
diode with a rectification factor as high as ~ 54 %. Finally, I will present the design and fabrication of Professor Sheng Shenbio-inspired brochosome structures with and without through-holes, which appear visually similar under Carnegie Mellon University
visible light but have their thermal emission profiles significantly distinct from each other. Such aproperty allows us to encode physical information with brochosome arrays that can only be decoded
under infrared signals, which is potentially useful in the areas of thermal encryption, infrared holograph,and data storage.
Biography: Sheng Shen is a Professor at the Mechanical Engineering Department of Carnegie Mellon University (CMU). He also holds
courtesy appointments in both the Electrical and Computer Engineering and the Materials Science and Engineering Departments at CMU.
He received his PhD degree from the Mechanical Engineering Department, MIT, in 2010. Prior to joining CMU in 2011, he conducted his
postdoctoral research at UC-Berkeley. His research interests include nanoscale heat transfer and energy conversion, nanophotonics, and theirapplications in energy conversion, thermal management, sensing, and multifunctional materials. Professor Shen is a recipient of NSF
CAREER Award, DARPA Director's Fellowship, DARPA Young Faculty Award, and Elsevier/JQSRT Raymond Viskanta Award forSpectroscopy and Radiative Transfer. He also received the CMU Dean's Early Career Fellowship, the Philomathia Foundation ResearchFellowship in Alternative Energy Research from UC-Berkeley, a Hewlett-Packard Best Paper Award from ASME Heat Transfer Division,and a Best Paper Award in Julius Springer Forum on Applied Physics.
主催：本件連絡先：

東京大学大学院工学系研究科専攻間横断型教育プログラム 機械システム・イノベーション （GMSI)
未来社会協創国際卓越大学院 (WINGS CFS)
量子科学技術国際卓越大学院 (WINGS-QSTEP)
統合物質・科学国際卓越大学院（MERIT-WINGS）
高齢社会総合研究国際卓越大学院（WINGS-GLAFS）
工学系WINGS産学協創教育推進基金
東京大学大学院工学系研究科総合研究機構 教授 塩見 淳一郎
GMSI事務局 E-mail: office@gmsi.t.u-tokyo.ac.jp Phone: 03-5841-0696