Researchers at VTT Technical Research Centre of Finland have successfully demonstrated a new electronic refrigeration technology that could enable major leaps in the development of quantum computers. The new electronic cooling technology could replace these cryogenic liquid mixtures and enable miniaturization of quantum computers.
In the experiment the researchers suspended a piece of silicon from such junctions and refrigerated the object by feeding electrical current from one junction to another through the piece. The current lowered the thermodynamic temperature of the silicon object as much as 40% from that of the surroundings.
The team demonstrated the effect by using semiconductor-superconductor junctions to refrigerate a silicon chip. In these junctions, the forbidden electronic states in the superconductor form a barrier over which the electrons from the semiconductor have to climb to drive the heat away. At the same time, the junction itself scatters or blocks the phonons so effectively that the electronic current can introduce a significant temperature difference over the junction.
This could lead to the miniaturization of future quantum computers, as it can simplify the required cooling infrastructure significantly.
The discovery has been published in Science Advances.