PhD defense: Dags Olsteins

Cryogenic On-Chip Multiplexing Using SAG Nanowires

Even though scalability of quantum electronics platforms and circuits is a commonly discussed aspect, a limiting factor for any materials platform is the number of transmission lines in cryogenic measurement setups which is limited by the available cooling power. Multiplexer circuits overcome this limitation by using control lines to address an exponential number of outputs. The operation and fault-tolerance of such circuits is presented and the circuits are then used to investigate the variability of nominally identical transistors based on selective area growth nanowires with statistical significance and the reproducibility of gate-defined quantum dot device parameters across nanowires. Additionally, the circuits are used to study the effect of systematic variations in nanowire geometry and structure on the electron transport properties.