Non-Local Propagation of Correlations in Quantum Systems with Long-Range Interactions
Abstract
The maximum speed with which information can propagate in a quantum many-body system directly affects how quickly disparate parts of the system can become correlated and how difficult the system will be to describe numerically. For systems with only short-range interactions, Lieb and Robinson derived a constant-velocity bound that limits correlations to within a linear effective light cone. However, little is known about the propagation speed in systems with long-range interactions, because analytic solutions rarely exist and because the best long-range bound is too loose to accurately describe the relevant dynamical time scales for any known spin model. Here we apply a variable-range Ising spin chain Hamiltonian and a variable-range XY spin chain Hamiltonian to a far-from-equilibrium quantum many-body system and observe its time evolution. For several different interaction ranges, we determine the spatial and time-dependent correlations, extract the shape of the light cone and measure the velocity with which correlations propagate through the system. This work opens the possibility for studying a wide range of many-body dynamics in quantum systems that are otherwise intractable.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 10, 2014
- Accession Number
- AD1003491
Entities
People
- Aaron Lee
- Alexey V Gorshkov
- Christopher Monroe
- Crystal Senko
- Jacob Smith
- Michael Foss-feig
- Philip Richerme
- Spyridon Michalakis
- Zhe-Xuan Gong
Organizations
- University of Maryland