QDev Seminar: James Colless

Frequency Multiplexing and Dispersive Gate Sensing in Quantum Dot Systems and Beyond

The last decade has been spent trying to understand how to create and manipulate single qubits, the analog of classical bits and the fundamental building block of any quantum computer. Recently an evolution has begun beyond these simple single qubit devices towards more complex multi-qubit arrays. Extracting information from these larger systems using conventional readout techniques is impractical for a number of reasons related to realisable device geometries, cryogenic space constraints and bandwidth limitations.

This talk will focus on the development of enabling readout technologies including dispersive gate sensing and frequency and time-domain multiplexing techniques. Together these can potentially form the basis of a highly scalable readout scheme capable of supporting 1000s of semiconductor spin qubits. Initial proof-of-concept steps towards such an architecture are demonstrated and future possibilities discussed.