Topological rejection of noise by quantum skyrmions
Pedro Ornelas, Isaac Nape, Robert de Mello Koch, Andrew Forbes
Abstract
An open challenge in the context of quantum information processing and communication is improving the robustness of quantum information to environmental contributions of noise, a severe hindrance in real-world scenarios. Here, we show that quantum skyrmions and their nonlocal topological observables remain resilient to noise even as typical entanglement witnesses and measures of the state decay. This allows us to introduce the notion of digitization of quantum information based on our discrete topological quantum observables, foregoing the need for robustness of entanglement. We compliment our experiments with a full theoretical treatment that unlocks the quantum mechanisms behind the topological behavior, explaining why the topology leads to robustness. Our approach holds exciting promise for intrinsic quantum information resilience through topology, highly applicable to real-world systems such as global quantum networks and noisy quantum computers. Recent work reported a non-local quantum entangled state of photons with skyrmionic topology. Here the authors demonstrate theoretically and experimentally that topological properties of this system are resilient to noise, even as entanglement measures decay, and elucidate the mechanisms behind this robustness.