Finite Speed of Quantum Scrambling with Long Range Interactions
- Creators
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Chen, Chi-Fang
- Lucas, Andrew
Abstract
In a locally interacting many-body system, two isolated qubits, separated by a large distance r, become correlated and entangled with each other at a time t≥r/v. This finite speed v of quantum information scrambling limits quantum information processing, thermalization, and even equilibrium correlations. Yet most experimental systems contain long range power-law interactions—qubits separated by r have potential energy V(r)∝r^(−α). Examples include the long range Coulomb interactions in plasma (α=1) and dipolar interactions between spins (α=3). In one spatial dimension, we prove that the speed of quantum scrambling remains finite for sufficiently large α. This result parametrically improves previous bounds, compares favorably with recent numerical simulations, and can be realized in quantum simulators with dipolar interactions. Our new mathematical methods lead to improved algorithms for classically simulating quantum systems, and improve bounds on environmental decoherence in experimental quantum information processors.
Additional Information
© 2019 American Physical Society. Received 15 August 2019; published 20 December 2019. We thank Alexey Gorshkov, Andrew Guo, and Minh Tran for pointing out an error in a previous version of the Letter. This work was supported by the Gordon and Betty Moore Foundation's EPiQS Initiative through Grant No. GBMF4302.Attached Files
Published - PhysRevLett.123.250605.pdf
Submitted - 1907.07637.pdf
Supplemental Material - longrange_v20_supplementonly.pdf
Files
Additional details
- Eprint ID
- 100389
- Resolver ID
- CaltechAUTHORS:20191220-102009312
- Gordon and Betty Moore Foundation
- GBMF4302
- Created
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2019-12-20Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field