Enhanced performance thermal diode via thermal boundary resistance at nanoscale

Hypothetically, a thermal rectifier is a device which leads a greater heat flux in one direction than another one, similarly as the electrical diode works for the electrical flux. Here, a drastic increment in the rectification factor has been obtained in nanoscale layered thermal diodes due to the effect of thermal boundary resistance present on an asymmetrical stack of nanofilms. Measurements show a thermal rectification factor as large as 3.3 under a temperature bias well below 1 K, which is the biggest thermal rectification factor reported at room temperature compared to previously reported thermal diodes so far, According to the direction of the applied heat flux, the observed impact of the thermal boundary resistance on the device is manifested through the presence of an asymmetric temperature rise along the heat transfer axis. Such effect provides an alternative route for the development of high performance thermal diodes. (C) 2015 AIP Publishing LLC.