Variational methods for contracting projected entangled-pair states
Laurens Vanderstraeten, Lander Burgelman, Boris Ponsioen, Maarten Van Damme, Bram Vanhecke, Philippe Corboz, Jutho Haegeman, Frank Verstraete
Abstract
Projected entangled-pair states (PEPS) provide excellent variational wave functions for ground states of strongly correlated quantum systems in two dimensions. Determining the expectation value of such a PEPS wave function requires the contraction of a two-dimensional tensor network. Here, the authors show that this contraction can itself be formulated as a variational problem, allowing one to compare the accuracies of two commonly used contraction schemes. The authors find good agreement between the different schemes, demonstrating the robustness of PEPS simulations.
Topics & Concepts
PhysicsTheoretical physicsComputer scienceQuantum mechanicsMathematicsQuantum many-body systemsPhysics of Superconductivity and MagnetismQuantum and electron transport phenomena