1. School of Physics, UNSW, Sydney 2052, Australia
2. School of Electrical Engineering and Telecommunications, UNSW, Sydney 2052, Australia
3. Centre for Engineered Quantum Systems (EQuS), School of Physics, UNSW, Sydney 2052, Australia
4. Australian Centre of Excellence for Quantum Computation and Communication Technology (CQC2T), UNSW, Sydney 2052, Australia