Just as a voltage difference can generate electric current, a temperature difference can generate a current flow in thermoelectric materials governed by its “Peltier conductivity” ℗. Now, researchers from Japan demonstrate an unprecedented large P in a single crystal of Ta₂PdSe₆ that is 200 times larger than the maximum P commercially available, opening doors to new research avenues and revolutionizing modern electronics.

We know that current flows inside a metallic conductor in presence of a voltage difference across its ends. However, this is not the only way to generate current. In fact, a temperature difference could work as well. This phenomenon, called “Seebeck effect,” laid the foundation of the field of thermoelectrics, which deals with materials producing electricity under the application of a temperature difference.

Similar to the concept of an electrical conductivity, thermoelectricity is governed by the Peltier conductivity, P, which relates the thermoelectric current to the temperature gradient. However, unlike its electrical counterpart, P is less explored and understood. For instance, is there a theoretical upper limit to how large P can be? Far from being a mere curiosity, the possibility of a large P could be a game changer for modern-day electronics.