A diagrammatic approach to strongly correlated fermions
KTH/Nordita/SU seminar in Theoretical Physics
Wednesday 18 January 2017
to 12:00 at
Johan Carlström (University of Massachusetts, Amherst)
Diagrammatic techniques remain one of the central tools for analysing quantum many-body systems. While these methods were originally only used in the context of analytical calculations, they are increasingly employed in combination with stochastic sampling. Diagrammatic Monte Carlo allows unbiased and controllable calculations to be carried out directly in the macroscopic limit, to a higher order than was ever possible by hand. Recently, a number of transformation techniques have broadened the range of systems that can be addressed with this method to include for example frustrated spins. I will discuss how spin-charge transformation and fermionisation techniques can be used to access the strongly correlated regime in fermionic lattice models.