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Published on: November 12, 2013
Non-local propagation of correlations in quantum systems with long-range interactions
Philip Richerme1, Zhe-Xuan Gong1, Aaron Lee1
1Joint Quantum Institute, University of Maryland Department of Physics and National Institute of Standards and Technology, College Park, Maryland 20742, USA.
Information propagation speed in quantum systems with long-range interactions is crucial for understanding correlations and numerical simulations. This study analyzes variable-range spin chains to measure correlation propagation, revealing insights into otherwise intractable quantum many-body dynamics.
Area of Science:
- Quantum many-body physics
- Condensed matter theory
- Statistical mechanics
Background:
- The maximum speed of information propagation, or quantum speed limit, dictates correlation dynamics in quantum systems.
- Existing bounds (e.g., Lieb-Robinson) are established for short-range interactions, limiting understanding of long-range systems.
- Analytic solutions are rare for long-range interacting systems, hindering accurate dynamical timescale descriptions.
Purpose of the Study:
- To investigate information propagation speeds in quantum many-body systems with variable long-range interactions.
- To determine the shape of the effective 'light cone' and measure correlation propagation velocities.
- To provide a framework for studying dynamics in complex quantum systems.
Main Methods:
- Application of variable-range Ising and XY spin chain Hamiltonians.
- Simulation of far-from-equilibrium quantum many-body system time evolution.
- Analysis of spatial and time-dependent correlations to extract light cone properties and propagation velocities.
Main Results:
- Quantification of correlation propagation speeds across different interaction ranges in the studied spin models.
- Empirical determination of the effective 'light cone' shape for variable long-range interactions.
- Demonstration of a method to study dynamics in systems previously considered intractable.
Conclusions:
- The study provides crucial insights into the dynamics of quantum many-body systems with long-range interactions.
- The developed methods enable the exploration of a wider range of quantum phenomena and system types.
- This research advances the understanding of information transport and correlation spreading in complex quantum systems.
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