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DOE OSTI · 1980217

Lieb-Robinson Light Cone for Power-Law Interactions

Tran, Minh C.·Guo, Andrew Y.·Baldwin, Christopher L.·Ehrenberg, Adam·Gorshkov, Alexey V.·Lucas, Andrew
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Abstract

The Lieb-Robinson theorem states that information propagates with a finite velocity in quantum systems on a lattice with nearest-neighbor interactions. What are the speed limits on information propagation in quantum systems with power-law interactions, which decay as 1 / r α at distance r ? Here, we present a definitive answer to this question for all exponents α > 2 d and all spatial dimensions d . Schematically, information takes time at least r min { 1 , α - 2 d } to propagate a distance r . As recent state transfer protocols saturate this bound, our work closes a decades-long hunt for optimal Lieb-Robinson bounds on quantum information dynamics with power-law interactions.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSPhysicsdipolar interactionlattice models in statistical physicsmathematical physicsquantum communicationquantum information processingquantum state transfer

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Tran, Minh C., Guo, Andrew Y., Baldwin, Christopher L., Ehrenberg, Adam, Gorshkov, Alexey V., Lucas, Andrew. 2021-10-11. Lieb-Robinson Light Cone for Power-Law Interactions. https://doi.org/10.1103/physrevlett.127.160401

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