Alexander, BBollinger, JJUys, Hermann2021-04-062021-04-062020-06Alexander, B., Bollinger, J. & Uys, H. 2020. Generating Greenberger-Horne-Zeilinger states with squeezing and postselection. <i>Physical Review A, 101.</i> http://hdl.handle.net/10204/119402469-99262469-9934https://arxiv.org/abs/1911.12404DOI:10.1103/PhysRevA.101.062303http://hdl.handle.net/10204/11940Many 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 via one-axis twisting, quantum measurement, and postselection, generates highly entangled multipartite states, which we refer to as projected squeezed (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 (GHZ) states. The method leads to an appreciable decrease in the state preparation time of GHZ states for successfully postselected outcomes when compared to preparation through unitary evolution with one-axis twisting only.AbstractenGreenberger-Horne-ZeilingerGHZQuantum state preparation methodsArticleAlexander, B., Bollinger, J., & Uys, H. (2020). Generating Greenberger-Horne-Zeilinger states with squeezing and postselection. <i>Physical Review A, 101</i>, http://hdl.handle.net/10204/11940Alexander, B, JJ Bollinger, and Hermann Uys "Generating Greenberger-Horne-Zeilinger states with squeezing and postselection." <i>Physical Review A, 101</i> (2020) http://hdl.handle.net/10204/11940Alexander B, Bollinger J, Uys H. Generating Greenberger-Horne-Zeilinger states with squeezing and postselection. Physical Review A, 101. 2020; http://hdl.handle.net/10204/11940.TY - Article AU - Alexander, B AU - Bollinger, JJ AU - Uys, Hermann AB - 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 via one-axis twisting, quantum measurement, and postselection, generates highly entangled multipartite states, which we refer to as projected squeezed (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 (GHZ) states. The method leads to an appreciable decrease in the state preparation time of GHZ states for successfully postselected outcomes when compared to preparation through unitary evolution with one-axis twisting only. DA - 2020-06 DB - ResearchSpace DP - CSIR J1 - Physical Review A, 101 KW - Greenberger-Horne-Zeilinger KW - GHZ KW - Quantum state preparation methods LK - https://researchspace.csir.co.za PY - 2020 SM - 2469-9926 SM - 2469-9934 T1 - Generating Greenberger-Horne-Zeilinger states with squeezing and postselection TI - Generating Greenberger-Horne-Zeilinger states with squeezing and postselection UR - http://hdl.handle.net/10204/11940 ER -24091