Date/Time Date(s) - 11/02/20222:30 pm - 3:30 pm
Categories
Today, there is a growing class of magnetic materials where it is believed that the interactions are bond-dependent in a way first imagined by Alexei Kitaev thereby opening a way for realizing topological phases. However, in these Kitaev materials other interactions are also often present, among them the well known Heisenberg coupling and also off-diagonal Gamma (?) terms giving rise to an unusally rich phase diagram. Even for the simplest models of Kitaev materials it is extremely difficult to arrive at a precise understanding of this complex phase-diagram. Hence, in order to obtain accurate results it is often useful to restrict the analysis to low-dimensions and here we mainly discuss two-leg ladders. Using matrix product states it is possible to determine the phase-diagram of such ladder systems with very high precision including the effects of a magnetic field in the [111] direction. An abundance of new phases appear. In this talk I will focus on some of these phases where a so-called string-order is present and others where chiral ordering appear. I will try to make connections to experiments where possible.
Erik Sorensen is a Professor at McMaster University in the department of Physics and Astronomy. He received his MSc from the University of AArhus, Denmark and his Ph. D. degree from the University of California Santa Cruz in 1992. He carried out postdoctoral research at the University of British Columbia and University of Indiana, Bloomington and in 1996 he became a professor in the Theoretical Physics group at Universite Paul Sabatier in Toulouse, France. In 2001 he joined McMaster University as a SHARCnet chair in computational physics. His research centres on computational techniques for studying quantum materials with strong correlations. In particular, he has played a major role in the application of density matrix renormalization group and quantum Monte Carlo techniques to the study of these materials. He has served on NSERC panels and other review committees and has held visiting position at Universite Paris Sud, Orsay among others.