Spins in SiMOS quantum dots are a promising candidate for a scalable qubit architecture. In our research lab, they are often read out using a radio-frequency single-electron transistor (RF-SET), where the source contact of the SET is connected to an RF tank circuit.

A change in resistance of the SET (Coulomb blockade vs. non-blockaded) will then change the signal amplitude of an RF tone that is reflected by the tank circuit. The reflected signal is separated from the incoming signal using a directional coupler and then amplified by a cryo amplifier. Currently, we only have one RF-SET connected per amplifier. The topic of this project is to develop a frequency multiplexing method to connect several amplifiers to the same amplifier. This will include the design and simulation of the circuit, making and ordering a test printed-circuit board (PCB), and performing characterisation of the circuit.

School

Electrical Engineering and Telecommunications

Research Area

Quantum | semiconductor devices | Radiofrequency Engineering

  • SiMOS Quantum Lab (UNSW/Diraq)

At the end of the project, the student will have developed and tested a circuit that connects several radio-frequency tank circuits to the same feedline and amplifier via frequency multiplexing.

Students will have access to a chemical engineering fluid foundry, gaining valuable collaborative skills. The data generated will be used in peer-reviewed publications, and students have the opportunity to further pursue this project as their honours thesis.