Observation of information flow in the anti-𝒫𝒯-symmetric system with nuclear spins

Abstract The recently theoretical and experimental researches on PT PT -symmetric system have attracted unprecedented attention because of the various interesting features and potential applications in extending canonical quantum mechanics. However, as the counterpart of PT PT -symmetry, there are few experimental researches on the anti- PT PT -symmetric quantum system because of the challenges in simulating anti- PT PT -symmetry in experiment. Here, we propose an algorithm for simulating the generalized anti- PT PT -symmetric system in the quantum circuit model. Utilizing the algorithm, we demonstrated the quantum simulation of anti- PT PT system experimentally, and an oscillation of information flow is observed in a nuclear magnetic resonance quantum simulator. The experiment showed that the information could recover from the environment completely when the anti- PT PT -symmetry is broken, whereas no information can be retrieved in the symmetry-unbroken phase. Our work opens the gate for the practical quantum simulation and experimental investigation of universal anti- PT PT -symmetric system in a quantum computer.