Chiral spin liquids in SU(N) fermionic Mott insulators with artifical gauge fields

Condensed Matter Seminars

Speaker: Miklos Lajko, Ecole Polytechnique Federale de Lausanne
Date & Time: January 20, 2017 2:00 - 3:00
Location: Hennigns 309
Local Contact: Ian Affleck
Intended Audience: Graduate

With the recent progress towards achieving SU(N) symmetry with ultracold fermionic atoms [1], the investigation of the effective SU(N) Heisenberg model on various one- and two-dimensional lattices has become a very active field of research. The appearance of chiral phases in these systems was first proposed by Hermele et al. [2] showing that chiral phases may stabilize in a special large-N limit with increasing number of particles per site. In my talk I will present our latest results confirming    that chiral phases may appear already in the one fermion per site limit in the presence of an artifical gauge field.  This is demonstrated for values of N ranging from 3 to 9 by an extensive study using exact diagonalization and Gutzwiller projected wave functions of the third-order effective model on the triangular lattice including 3-site permutations around plaquettes [3]. The parton construction is based on a set of N Gutzwiller projected fermionic wave functions that emerge naturally from varying the boundary conditions of a Hofstadter-type mean field Hamiltonian. We also tested the SU(6) honeycomb model, and found that a chiral phase is realized in the presence of finite ring exchange interaction around plaquettes [4].

References:

[1] M. A. Cazalilla and A. M. Rey, Rep. Prog. Phys. 77, 124401 (2014)
[2] M. Hermele, V. Gurarie, A. M. Rey, Phys. Rev. Lett. 103, 135301 (2009)
[3]  P. Nataf, M. Lajkó, A. Wietek, K. Penc, F. Mila, and A. M. Läuchli,  Phys. Rev. Lett. 117, 167202
[4] P. Nataf, M. Lajkó, P. Corboz, A. M. Läuchli, K. Penc, and F. Mila,Phys. Rev. B 93, 201113(R)