Nanosized Electronic Cooler Combined with Superconducting Proximity Effect Thermometry

Abstract

Electronic coolers have the potential to lower the temperature of mesoscopic electronic systems well below the lattice temperature with the final goal to reach ultimately an electronic temperature in the 10 mK range. A challenging task is to design a reliable electronic thermometry for this temperature range, including extremely low power dissipation, good sensitivity and preferably a theoretical description of the response with few experimentally determined parameters. We present an experimental realization and characterization of a nano sized electronic cooler with a superconducting proximity effect thermometer. We demonstrate an improved operation mode of the thermometer using escape statistics from the superconducting to the normal state.