2014/01/31 by J. Kaczmarczyk
Physics and Astronomy · #Diagrammatic reasoning #Energy (signal processing) #Ground state #Hamiltonian (control theory) #Minification #Nuclear physics research studies #Physics of Superconductivity and Magnetism #Quantum many-body systems #Simple (philosophy) #Wave function #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1080/14786435.2014.965235
11 pages, 1 figure
arxiv created 2014/07/26 · openalex publication_date 2014/10/14 · arxiv updated 2014/11/24 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In this work, we analyse the variational problem emerging from the Gutzwiller approach to strongly correlated systems. This problem comprises two main steps: evaluation and minimization of the ground state energy for the postulated Gutzwiller Wave Function. We discuss the available methods for evaluating , in particular the recently proposed diagrammatic expansion method. We compare the two existing approaches to minimize : the standard approach based on the effective single-particle Hamiltonian and the so-called Statistically-consistent Gutzwiller Approximation (SGA). On the example of the superconducting phase analysis, we show that these approaches lead to the same minimum as it should be. However, the calculations within the SGA method are easier to perform and the two approaches allow for a simple cross-check of the obtained results. Finally, we show two ways of solving the equations resulting from the variational procedure, as well as how to incorporate the condition for a fixed number of particles.