SCL Seminar: Jakša Vućičević, 21 December 2016

You are cordially invited to the SCL seminar of the Center for the Study of Complex Systems, which will be held on Wednesday, 21 December 2016 at 11:30 in the library reading room “Dr. Dragan Popović" of the Institute of Physics Belgrade. The talk entitled

Beyond DMFT - capturing low temperature physics of the cuprates

will be given by Dr. Jaksa Vućičević (IPhT, CEA Saclay, France; Scientific Computing Laboratory, Center for the Study of Complex Systems, Institute of Physics Belgrade).

Abstract of the talk:

High-T_c cuprate superconductors exhibit puzzling behavior at low temperature, eluding full theoretical understanding for 30 years. The main challenge lies in proper treatment of non-local correlations which give rise to d-wave pairing and the normal-phase pseudogap. The 2D Hubbard model on a square lattice is widely considered to be the right starting point for the description of the cuprates, but its (numerically) exact solutions are very few, and are obtained at an immense computational cost. In the first part of the talk, we will present an overview of the ongoing efforts to identify the minimal method to properly solve the Hubbard model at low temperature. The recently developed TRILEX and nested-cluster DMFT show the most promise in direct comparison to the large-scale DCA calculations. In the second part of the talk, we will employ TRILEX and its simplifications EDMFT+GW and GW for exploratory work, uncover a strong link between the prominence of collective spin-fluctuations and height of the superconducting T_c, and show how both strongly depend on the details of the bare electronic dispersion.