Date and Time: 24-June-2024（Monday）2:00pm (Beijing time)

Venue: Room 526

Speaker: Libin Wang, Aalto University, Finland

Host: Yulong Liu (BAQIS)

Title: Normal Metal Coulomb Blockade Thermometer

About the Speaker:

Libin Wang received his doctoral degree from Aalto University, Finland, in 2020. His doctoral research focused on studying thermal transport in mesoscopic devices at low temperatures using a proximity Josephson junction thermometer. After completing his Ph.D., he joined the University of Basel in Switzerland as a postdoctoral researcher, where he worked on the superconducting Al/InAs quantum well material platform to explore its applications in Andreev (spin) qubits. In 2022, Libin returned to Finland to join Aalto University as a staff scientist. His current research focus on developing techniques at cryogenic temperatures.

Abstract:

The Coulomb Blockade Thermometer (CBT) was first proposed and experimentally investigated as a primary thermometer in 1994. Since then, its temperature measurement range has been extended from tens of Kelvin down to below 1 mK. Traditionally, CBTs are fabricated with superconducting Al junctions, requiring an external magnetic field to suppress its superconductivity below the critical temperature, thus limiting their applications. In this talk, I will present a CBT based on normal metals. Through optimization of sample thermalization and measurement filtering, we have achieved electron temperature measurements below 10 mK. This normal metal CBT can be used for optimizing measurement setup, measuring local on-chip temperatures. and potentially replacing widely used secondary thermometers in the market.