2013/04/30 by Philipp Hauke, Luca Tagliacozzo · 3 citations
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Ising model #Light cone #Physics #Quantum #Quantum and electron transport phenomena #Quantum computer #Quantum entanglement #Quantum many-body systems #Quantum mechanics #Quantum simulator #Range (aeronautics) #Statistical physics #cond-mat.quant-gas #cond-mat.stat-mech #cond-mat.str-el #quant-ph
paper · pdf · doi:10.1103/physrevlett.111.207202
published as Phys. Rev. Lett. 111, 207202 (2013) · 4 pages + Supplemental Material, 3+1 Figures. v2: revised introduction and conclusion. Accepted in Phys. Rev. Lett
arxiv created 2013/10/16 · openalex publication_date 2013/11/12 · arxiv updated 2013/11/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The nonequilibrium response of a quantum many-body system defines its fundamental transport properties and how initially localized quantum information spreads. However, for long-range-interacting quantum systems little is known. We address this issue by analyzing a local quantum quench in the long-range Ising model in a transverse field, where interactions decay as a variable power law with distance ∝r(-α), α>0. Using complementary numerical and analytical techniques, we identify three dynamical regimes: short-range-like with an emerging light cone for α>2, weakly long range for 1<α<2 without a clear light cone but with a finite propagation speed of almost all excitations, and fully nonlocal for α<1 with instantaneous transmission of correlations. This last regime breaks generalized Lieb-Robinson bounds and thus locality. Numerical calculation of the entanglement spectrum demonstrates that the usual picture of propagating quasiparticles remains valid, allowing an intuitive interpretation of our findings via divergences of quasiparticle velocities. Our results may be tested in state-of-the-art trapped-ion experiments.