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Measurement-induced quantum phases realized in a trapped-ion quantum computer



Michael Gullans, Alexey Gorshkov, David Huse, Christopher Monroe, Crystal Noel, Pradeep Niroula, Daiwei Zhu, Andrew Risinger, Laird Egan, Debopriyo Biswas, Marko Cetina


Many-body open quantum systems balance internal dynamics against decoherence from interactions with an environment. Here, we explore this balance via random quantum circuits implemented on a trapped-ion quantum computer, where the system evolution is represented by unitary gates with interspersed projective measurements. As the measurement rate is varied, a purification phase transition is predicted to emerge at a critical point akin to a fault- tolerent threshold. We probe the "pure" phase, where the system is rapidly projected to a deterministic state conditioned on the measurement outcomes, and the "mixed" or "coding" phase, where the initial state becomes partially encoded into a quantum error correcting codespace. We find evidence of the two phases and show numerically that, with modest system scaling, critical properties of the transition emerge.
Nature Physics


Quantum information science, phase transitions, error correction


Gullans, M. , Gorshkov, A. , Huse, D. , Monroe, C. , Noel, C. , Niroula, P. , Zhu, D. , Risinger, A. , Egan, L. , Biswas, D. and Cetina, M. (2022), Measurement-induced quantum phases realized in a trapped-ion quantum computer, Nature Physics, [online],, (Accessed May 29, 2024)


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Created June 2, 2022, Updated November 29, 2022