Title | Quantum information scrambling through a high-complexity operator mapping |
Publication Type | Journal Article |
Year of Publication | 2019 |
Authors | X. Li, G. Zhu, M. Han, and X. Wang |
Journal | Phys. Rev. A |
Volume | 100 |
Pagination | 032309 |
Date Published | SEP 6 |
Type of Article | Article |
ISSN | 2469-9926 |
Abstract | Quantum information scrambling has attracted much attention amid the effort to reconcile the conflict between quantum-mechanical unitarity and the thermalization irreversibility in many-body systems. Here we propose an unconventional mechanism to generate quantum information scrambling through a high-complexity mapping from logical to physical degrees-of-freedom that hides the logical information into nonseparable many-body correlations. Corresponding to this mapping, we develop an algorithm to efficiently sample a Slater-determinant wave function and compute all physical observables in dynamics with a polynomial cost in system size. The system shows information scrambling in the quantum many-body Hilbert space characterized by the spreading of Hamming distance. At late time we find emergence of classical diffusion dynamics in this quantum many-body system. We establish that the operator mapping enabled growth in an out-of-time-order correlator exhibits exponential-scrambling behavior. The quantum information-hiding mapping approach may shed light on the understanding of fundamental connections among computational complexity, information scrambling, and quantum thermalization. |
DOI | 10.1103/PhysRevA.100.032309 |