2008/02/27 by Shreyoshi Mondal, Diptiman Sen, K. Sengupta · 6 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Correlation function (quantum field theory) #Exponent #Mathematical physics #Physics #Physics of Superconductivity and Magnetism #Quantum many-body systems #Quantum mechanics #Scaling #Statistical physics #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.045101
published as Phys. Rev. B 78, 045101 (2008) · 12 pages including 11 figures
arxiv created 2008/02/27 · openalex publication_date 2008/07/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study quench dynamics and defect production in the Kitaev and the extended Kitaev models. For the Kitaev model in one dimension, we show that in the limit of slow quench rate, the defect density n\ensuremath∼1/√\ensuremathτ, where 1/\ensuremathτ is the quench rate. We also compute the defect correlation function by providing an exact calculation of all independent nonzero spin correlation functions of the model. In two dimensions, where the quench dynamics takes the system across a critical line, we elaborate on the results of earlier work [K. Sengupta, D. Sen, and S. Mondal, Phys. Rev. Lett. 100, 077204 (2008)] to discuss the unconventional scaling of the defect density with the quench rate. In this context, we outline a general proof that for a d-dimensional quantum model, where the quench takes the system through a d\ensuremath-m dimensional gapless (critical) surface characterized by correlation length exponent \ensuremathν and dynamical critical exponent z, the defect density n\ensuremath∼1/\ensuremathτ^m\ensuremathν/(z\ensuremathν+1). We also discuss the variation of the shape and spatial extent of the defect correlation function with both the rate of quench and the model parameters and compute the entropy generated during such a quenching process. Finally, we study the defect scaling law, entropy generation and defect correlation function of the two-dimensional extended Kitaev model.