Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System

Autor:	Horacio M. Pastawski, K. X. Wei, Ana Karina Chattah, L. Buljubasich, Claudia M. Sánchez, Paola Cappellaro
Rok vydání:	2020
Předmět:	Physics Quantum dynamics General Physics and Astronomy Perturbation (astronomy) purl.org/becyt/ford/1.3 [https] LOSCHMIDT 01 natural sciences NMR Many body purl.org/becyt/ford/1 [https] 0103 physical sciences QUANTUM DYNAMICS 010306 general physics SCALING Scaling Mathematical physics
Zdroj:	CONICET Digital (CONICET) Consejo Nacional de Investigaciones Científicas y Técnicas instacron:CONICET
ISSN:	1079-7114 0031-9007
DOI:	10.1103/physrevlett.124.030601
Popis:	When a qubit or spin interacts with others under a many-body Hamiltonian, the information it contains progressively scrambles. Here, nuclear spins of an adamantane crystal are used as a quantum simulator to monitor such dynamics through out-of-time-order correlators, while a Loschmidt echo (LE) asses how weak perturbations degrade the information encoded in these increasingly complex states. Both observables involve the implementation of a time-reversal procedure which, in practice, involves inverting the sign of the effective Hamiltonian. Our protocols use periodic radio frequency pulses to modulate the natural dipolar interaction implementing a Hamiltonian that can be scaled down at will. Meanwhile, experimental errors and strength of perturbative terms remain constant and can be quantified through the LE. For each scaling factor, information spreading occurs with a timescale, T2, inversely proportional to the local second moment of the Hamiltonian. We find that, when the reversible interactions dominate over the perturbations, the information scrambled among up to 102 spins can still be recovered. However, we find that the LE decay rate cannot become smaller than a critical value 1/T3≈(0.15±0.02)/T2, which only depends on the interactions themselves, and not on the perturbations. This result shows the emergence of a regime of intrinsic irreversibility in accordance to a central hypothesis of irreversibility, hinted from previous experiments. Fil: Sánchez, Claudia Marina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina Fil: Chattah, Ana Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina Fil: Wei, K. X.. Massachusetts Institute of Technology; Estados Unidos Fil: Buljubasich Gentiletti, Lisandro. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina Fil: Cappellaro, P.. Massachusetts Institute of Technology; Estados Unidos Fil: Pastawski, Horacio Miguel. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::86261fa1d03d125e3bb9ac4a66d2bf98 https://doi.org/10.1103/physrevlett.124.030601 Zobrazit plný text záznamu