Choe Hwan Sung, Prabhakar Radhika, Wehmeyer Geoff, Allen Frances I, Lee Woochul, Jin Lei, Li Ying, Yang Peidong, Qiu Cheng-Wei, Dames Chris, Scott Mary, Minor Andrew, Bahk Je-Hyeong, Wu Junqiao
Department of Materials Science and Engineering , University of California , Berkeley , California 94720 , United States.
Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States.
Nano Lett. 2019 Jun 12;19(6):3830-3837. doi: 10.1021/acs.nanolett.9b00984. Epub 2019 May 13.
Considerable advances in manipulating heat flow in solids have been made through the innovation of artificial thermal structures such as thermal diodes, camouflages, and cloaks. Such thermal devices can be readily constructed only at the macroscale by mechanically assembling different materials with distinct values of thermal conductivity. Here, we extend these concepts to the microscale by demonstrating a monolithic material structure on which nearly arbitrary microscale thermal metamaterial patterns can be written and programmed. It is based on a single, suspended silicon membrane whose thermal conductivity is locally, continuously, and reversibly engineered over a wide range (between 2 and 65 W/m·K) and with fine spatial resolution (10-100 nm) by focused ion irradiation. Our thermal cloak demonstration shows how ion-write microthermotics can be used as a lithography-free platform to create thermal metamaterials that control heat flow at the microscale.
通过热二极管、伪装材料和隐身衣等人工热结构的创新，在控制固体中的热流方面已经取得了相当大的进展。这类热装置只能通过机械组装具有不同热导率值的不同材料，在宏观尺度上轻松构建。在此，我们通过展示一种单片材料结构，将这些概念扩展到微观尺度，在该结构上几乎可以写入和编程任意的微观尺度热超材料图案。它基于单个悬浮硅膜，通过聚焦离子辐照，其热导率在很宽的范围内（2至65瓦/米·开尔文）以精细的空间分辨率（10 - 100纳米）进行局部、连续且可逆的调控。我们的热隐身衣演示展示了离子写入微热学如何可以用作无光刻平台，以创建在微观尺度上控制热流的热超材料。
