Generating GHZ states with squeezing and post-selection
Byron Alexander, Hermann Uys, John Bollinger
Many quantum state preparation methods rely on a combination of dissipative quantum state initialization, followed by unitary evolution to a desired target state. Here we demonstrate the usefulness of quantum measurement as an additional tool for quantum state preparation. Starting from a pure separable multipartite state, a control sequence, which includes rotation, spin squeezing, quantum measurement and post-selection, generates a highly entangled multipartite state, which we refer to as Projected Squeezed states (or PS states). Through an optimization method, we then identify parameters required to maximize the overlap fidelity of the PS states with the maximally entangled Greenberger-Horne-Zeilinger states (or GHZ states). The method leads to an appreciable decrease in state preparation time of GHZ states when compared to preparation through unitary evolution only.
, Uys, H.
and Bollinger, J.
Generating GHZ states with squeezing and post-selection, Physical Review A, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=929193
(Accessed September 26, 2023)