How well can a prefabricated electrode contact a 2D crystal?
Low-temperature measurements showed that mechanical transfer can make highly transparent superconducting contacts. Electrode roughness limits their performance.
Scott Mills, Naomi Mizuno and colleagues compared two ways to make a contact with a 2D crystal. They fabricated electrodes on the crystal in one set of devices and transferred the crystal onto prefabricated electrodes in another. Superconducting electrodes let them probe how readily charge crossed the interface.
Mechanically assembled contacts could match the transparency of conventionally fabricated contacts and sometimes exceed it. Rough prefabricated electrodes limited that performance. Liyuan Zhang and Xu Du are the corresponding authors.