2012/03/31 by Victor Bapst, Guilhem Semerjian · 2 citations
Computer Science · Physics and Astronomy · #Adiabatic process #Ferromagnetism #Metastability #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum annealing #Quantum dynamics #Quantum many-body systems #Quantum phase transition #Quantum phases #Spinodal #Spins #cond-mat.dis-nn #cond-mat.stat-mech #quant-ph
paper · pdf · doi:10.1088/1742-5468/2012/06/p06007
published as J. Stat. Mech. P06007 (2012) · 44 pages, 23 figures
openalex publication_date 2012/06/19 · arxiv created 2012/07/25 · arxiv updated 2012/07/26 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
This paper deals with fully-connected mean-field models of quantum spins with p-body ferromagnetic interactions and a transverse field. For p=2 this corresponds to the quantum Curie-Weiss model (a special case of the Lipkin-Meshkov-Glick model) which exhibits a second-order phase transition, while for p>2 the transition is first order. We provide a refined analytical description both of the static and of the dynamic properties of these models. In particular we obtain analytically the exponential rate of decay of the gap at the first-order transition. We also study the slow annealing from the pure transverse field to the pure ferromagnet (and vice versa) and discuss the effect of the first-order transition and of the spinodal limit of metastability on the residual excitation energy, both for finite and exponentially divergent annealing times. In the quantum computation perspective this quantity would assess the efficiency of the quantum adiabatic procedure as an approximation algorithm.