Coherent control via weak measurements in P-31 single-atom electron and nuclear spin qubits


JT Muhonen ,JP Dehollain, A Laucht, S Simmons, R Kalra, FE Hudson, AS Dzurak, A Morello, DN Jamieson, JC McCallum, KM Itoh

Phys. Rev. B, 98, 155201 (2018)

Coherent control via weak measurements in P-31 single-atom electron and nuclear spin qubits

The understanding of weak measurements and interaction-free measurements has greatly expanded the conceptual and experimental toolbox to explore the quantum world. Here we demonstrate single-shot variable-strength weak measurements of the electron and the nuclear spin states of a single 31P donor in silicon. We first show how the partial collapse of the nuclear spin due to measurement can be used to coherently rotate the spin to a desired pure state. We explicitly demonstrate that phase coherence is preserved throughout multiple sequential single-shot weak measurements, and that the partial state collapse can be reversed. Second, we use the relation between measurement strength and perturbation of the nuclear state as a physical meter to extract the tunneling rates between the 31P donor and a nearby electron reservoir from data, conditioned on observing no tunneling events. Our experiments open avenues to measurement-based state preparation, steering and feedback protocols for spin systems in the solid state, and highlight the fundamental connection between information gain and state modification in quantum mechanics.

University: UNSW Sydney, University of Melbourne

Authors Centre Participants: Dr. Arne Laucht, Dr. Fay E. Hudson, Prof. Andrew S. Dzurak, Prof. Andrea Morello, Prof. David N. Jamieson, A. Prof. Jeff McCallum, JT Muhonen,JP Dehollain, S Simmons, R Kalra, KM Itoh

Source: Physical Review B

Publication Type: Refereed Journal article

DOI Link: DOI Link

Filter By
Publication Type