Quantum adiabatic cycles and their breakdown
Year: 2021
Authors: Defenu N.
Autors Affiliation: Swiss Fed Inst Technol, Inst Theoret Phys, Zurich, Switzerland.
Abstract: While the Landau-Zener problem is conventionally used to describe defects formation in quantum systems, it cannot be applied to non-interacting Bose excitations as the adiabatic perturbation theory assumptions are violated by Bose statistics. Here, the author investigates adiabatic cycles across quantum critical points with harmonic Bose quasi-particles and shows that adiabaticity breakdown is a universal feature of these systems The assumption that quasi-static transformations do not quantitatively alter the equilibrium expectation of observables is at the heart of thermodynamics and, in the quantum realm, its validity may be confirmed by the application of adiabatic perturbation theory. Yet, this scenario does not straightforwardly apply to Bosonic systems whose excitation energy is slowly driven through the zero. Here, we prove that the universal slow dynamics of such systems is always non-adiabatic and the quantum corrections to the equilibrium observables become rate independent for any dynamical protocol in the slow drive limit. These findings overturn the common expectation for quasi-static processes as they demonstrate that a system as simple and general as the quantum harmonic oscillator, does not allow for a slow-drive limit, but it always displays sudden quench dynamics.
Journal/Review: COMMUNICATIONS PHYSICS
Volume: 4 (1) Pages from: 150-1 to: 150-6
More Information: I acknowledge fruitful discussions with T. Enss, G.M. Graf, M. Kastner and G. Morigi on this problem. I also thank T. Enss, G. Gori, G.M. Graf and A. Trombettoni for a critical reading of the paper. This work is supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy EXC2181/1-390900948 (the Heidelberg STRUCTURES Excellence Cluster).KeyWords: Body Approximation Methods; Solvable Model; Cosmological Experiments; Validity; Renormalization; Coherence; Symmetry; Dynamics; LimitDOI: 10.1038/s42005-021-00649-6Citations: 4data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-10-20References taken from IsiWeb of Knowledge: (subscribers only)