Measurement-induced entanglement and teleportation on a noisy quantum processor.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37853150.
- Also identified by DOI 10.1038/s41586-023-06505-7 and PMC identifier 10584681.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Measurement has a special role in quantum theory<sup>1</sup>: by collapsing the wavefunction, it can enable phenomena such as teleportation<sup>2</sup> and thereby alter the 'arrow of time' that constrains unitary evolution. When integrated in many-body dynamics, measurements can lead to emergent patterns of quantum information in space-time<sup>3-10</sup> that go beyond the established paradigms for characterizing phases, either in or out of equilibrium<sup>11-13</sup>. For present-day noisy intermediate-scale quantum (NISQ) processors<sup>14</sup>, the experimental realization of such physics can be problematic because of hardware limitations and the stochastic nature of quantum measurement. Here we address these experimental challenges and study measurement-induced quantum information phases on up to 70 superconducting qubits. By leveraging the interchangeability of space and time, we use a duality mapping<sup>9,15-17</sup> to avoid mid-circuit measurement and access different manifestations of the underlying phases, from entanglement scaling<sup>3,4</sup> to measurement-induced teleportation<sup>18</sup>. We obtain finite-sized signatures of a phase transition with a decoding protocol that correlates the experimental measurement with classical simulation data. The phases display remarkably different sensitivity to noise, and we use this disparity to turn an inherent hardware limitation into a useful diagnostic. Our work demonstrates an approach to realizing measurement-induced physics at scales that are at the limits of current NISQ processors.