  Heat engines made of quantum-dot (QD) superlattice nanowires (SLNWs) offer
promising applications in energy harvesting due to the reduction of phonon
thermal conductivity. In solid state electrical generators (refrigerators), one
needs to generate (remove) large amount of charge current (heat current).
Consequently, a high QD SLNW density is required for realistic applications.
This study theoretically investigated the properties of power factor and
electron heat rectification for an SLNW array under the transition from a one
dimensional system to a two dimensional system. The SLNW arrays show the
functionality of heat diodes, which is mainly attributed to a transmission
coefficient with a temperature-bias direction dependent characteristic.
