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arXiv · 2401.13735

Entanglement assisted probe of the non-Markovian to Markovian transition in open quantum system dynamics

Chandrashekhar Gaikwad·Daria Kowsari·Carson Brame·Xingrui Song·Haimeng Zhang·Martina Esposito·Arpit Ranadive·Giulio Cappelli·Nicolas Roch·Eli M. Levenson-Falk·Kater W. Murch
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Abstract

We utilize a superconducting qubit processor to experimentally probe non-Markovian dynamics of an entangled qubit pair. We prepare an entangled state between two qubits and monitor the evolution of entanglement over time as one of the qubits interacts with a small quantum environment consisting of an auxiliary transmon qubit coupled to its readout cavity. We observe the collapse and revival of the entanglement as a signature of quantum memory effects in the environment. We then engineer the non-Markovianity of the environment by populating its readout cavity with thermal photons to show a transition from non-Markovian to Markovian dynamics, ultimately reaching a regime where the quantum Zeno effect creates a decoherence-free subspace that effectively stabilizes the entanglement between the qubits.

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Chandrashekhar Gaikwad, Daria Kowsari, Carson Brame, Xingrui Song, Haimeng Zhang, Martina Esposito, Arpit Ranadive, Giulio Cappelli, Nicolas Roch, Eli M. Levenson-Falk, Kater W. Murch. 2024-01-24. Entanglement assisted probe of the non-Markovian to Markovian transition in open quantum system dynamics. https://doi.org/10.1103/physrevlett.132.200401

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