Simulation of fermionic lattice models in two dimensions with tensor network algorithms ?

by Philippe Corboz (Brisbane, Australia)

Wednesday 17 Feb 2010, 11:15 → 12:15 Europe/Zurich

EPFL, Salle N. 727 BSP

The simulation of strongly correlated fermionic systems in two dimensions is one of the biggest challenges in computational physics. Quantum Monte Carlo is very powerful for solving bosonic models, but it fails for fermionic systems because of the negative sign problem. In this talk I will present an approach to efficiently simulate fermionic systems in two dimensions, based on tensor network algorithms such as the multi-scale entanglement renormalization ansatz (MERA) and infinite projected pair-entangled states (iPEPS). These algorithms have been successfully applied to bosonic systems in past years, but not to fermionic systems until recently. I will introduce a particularly simple formalism to account for the statistics of fermionic degrees of freedom in a tensor network. Benchmark results for free and interacting fermions confirm the validity of this approach, and show that the computational cost of simulations does not depend a priori on the particle statistics, but on the amount of entanglement in the system.