Fiorino Anthony, Thompson Dakotah, Zhu Linxiao, Mittapally Rohith, Biehs Svend-Age, Bezencenet Odile, El-Bondry Nadia, Bansropun Shailendra, Ben-Abdallah Philippe, Meyhofer Edgar, Reddy Pramod
Department of Mechanical Engineering , University of Michigan , Ann Arbor , Michigan 48109 , United States.
Institut für Physik , Carl von Ossietzky Universität , D-26111 Oldenburg , Germany.
ACS Nano. 2018 Jun 26;12(6):5774-5779. doi: 10.1021/acsnano.8b01645. Epub 2018 May 23.
In this work we demonstrate thermal rectification at the nanoscale between doped Si and VO surfaces. Specifically, we show that the metal-insulator transition of VO makes it possible to achieve large differences in the heat flow between Si and VO when the direction of the temperature gradient is reversed. We further show that this rectification increases at nanoscale separations, with a maximum rectification coefficient exceeding 50% at ∼140 nm gaps and a temperature difference of 70 K. Our modeling indicates that this high rectification coefficient arises due to broadband enhancement of heat transfer between metallic VO and doped Si surfaces, as compared to narrower-band exchange that occurs when VO is in its insulating state. This work demonstrates the feasibility of accomplishing near-field-based rectification of heat, which is a key component for creating nanoscale radiation-based information processing devices and thermal management approaches.
在这项工作中，我们展示了掺杂硅与VO表面之间的纳米级热整流效应。具体而言，我们表明VO的金属-绝缘体转变使得当温度梯度方向反转时，硅和VO之间的热流能够产生很大差异。我们进一步表明，这种整流效应在纳米级间距下会增强，在约140 nm的间隙和70 K的温差下，最大整流系数超过50%。我们的模型表明，与VO处于绝缘状态时发生的窄带交换相比，这种高整流系数是由于金属VO与掺杂硅表面之间的热传递宽带增强所致。这项工作证明了实现基于近场的热整流的可行性，这是创建基于纳米级辐射的信息处理设备和热管理方法的关键组成部分。
