2014/09/30 by Ning Wu, Arun Nanduri, Herschel Rabitz · 2 citations
Engineering · Mathematics · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Critical point (mathematics) #Electrical engineering #Engineering #Geometry #Mathematics #Physics #Point (geometry) #Quantum #Quantum and electron transport phenomena #Quantum critical point #Quantum many-body systems #Quantum mechanics #Quantum phase transition #Statistical physics #Tipping point (physics) #cond-mat.quant-gas #cond-mat.str-el #quant-ph
paper · pdf · doi:10.1103/physrevb.91.041115
published as Phys. Rev. B 91, 041115(R) (2015) · 5 pages, 4 figures. The first two authors contributed equally to this work
arxiv created 2014/12/09 · openalex publication_date 2015/01/26 · arxiv updated 2015/01/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
The dynamics of quantum phase transitions are inevitably accompanied by the formation of defects when crossing a quantum critical point. For a generic class of quantum critical systems, we solve the problem of minimizing the production of defects through the use of a gradient-based deterministic optimal control algorithm. By considering a finite-size quantum Ising model with a tunable global transverse field, we show that an optimal power-law quench of the transverse field across the Ising critical point works well at minimizing the number of defects, in spite of being drawn from a subset of quench profiles. These power-law quenches are shown to be inherently robust against noise. The optimized defect density exhibits a transition at a critical ratio of the quench duration to the system size, which we argue coincides with the intrinsic speed limit for quantum evolution.