Dual-mode solid-state thermal rectification
Ramesh Shrestha, Yuxuan Luan, Xiao Luo, Sunmi Shin, Teng Zhang, Phil M. Smith, Wei Gong, Michael R. Bockstaller, Tengfei Luo, Renkun Chen, Kedar Hippalgaonkar, Sheng Shen
Abstract
Thermal rectification is an exotic thermal transport phenomenon which allows heat to transfer in one direction but block the other. We demonstrate an unusual dual-mode solid-state thermal rectification effect using a heterogeneous "irradiated-pristine" polyethylene nanofiber junction as a nanoscale thermal diode, in which heat flow can be rectified in both directions by changing the working temperature. For the nanofiber samples measured here, we observe a maximum thermal rectification factor as large as ~50%, which only requires a small temperature bias of <10 K. The tunable nanoscale thermal diodes with large rectification and narrow temperature bias open up new possibilities for developing advanced thermal management, energy conversion and, potentially thermophononic technologies.