Wataru Kobayashi at Waseda University in Japan and a few friends have built a rectifier that allows a heat current to travel in one direction but not the other.
For some time, it was believed that thermal rectifiers would be possible with materials which have thermal conductivities that change with temperature. The methodology is to find a material with a high thermal conductivity at low temperatures and a low thermal conductivity at high temperatures, and then to marry it with a material with exactly the opposite characteristic.
Cobalt oxides: LaCoO3 and La0.7Sr0.3CoO3 Glued together, form a diode-like device that allows a heat current to pass in one direction but not the other. Just like a normal diode lets current pass in one direction.
That’s impressive because it’s the first time anybody has demonstrated heat rectification in a bulk solid.
The inventors think about a one step further to this technology:
” Owing to the controllability of the heat current, the thermal rectifier can be utilized for future practical application such as a thermal transistor, thermal logic gates, and a thermal memory.”
Seems interesting. What do you think?