Multilayer Heater Nano-Cryotron: A Superconducting Nanowire-Based Thermal Switch

We demonstrate a multilayer nanoscale cryogenic heater-based switch (M-hTron) that uses a nor-mal metal heater overlapping a thin lm superconductor separated by a thin insulating layer. TheM-hTron eliminates leakage current found in three terminal superconducting switches and appliesheat locally to the superconductor, reducing the energy required to switch the device. Modelingusing the energy balance equations and the acoustic mismatch model demonstrates reasonable agree-ment with experiment. The M-hTron is a promising device for digital superconducting electronicsrequiring high fan-out and oers the possibility of enhancing readout for superconducting nanowiresingle-photon detectors.