Topic: The stability of the non-abelian topological phase in the Kitaev materials and quantum Hall systems
Speaker: Zheng ZHU (MIT)
The exotic phases in condensed matters, especially non-abelian topological phase, have spurred a wide variety of investigations in recent years. Typical examples of such phase have been proposed in Kitaev materials around equal coupling and quantum Hall liquid in a half-filled second Landau level. By combining density matrix renormalization group (DMRG) and exact diagonalization (ED), we study the stability of non-Abelian topological spin liquid phase in the two-dimensional (2D) Kitaev honeycomb model subject to a magnetic field, and the quantum Hall liquid in a half-filled second Landau level (n=1) against with band mass anisotropy. In the Kitaev systems, we characterize the topological phase based on the energy spectra, entanglement, topological degeneracy, and expectation values of Wilson loop operators, and more crucially, we find the antiferromagnetic (AFM) Kitaev spin liquid remains robust up to a magnetic field that is an order of magnitude larger than ferromagnetic (FM) one. In the quantum Hall system, We analyze the energy spectrum, guiding center structure factors, and find increasing the mass anisotropy induces a quantum phase transition from the Moore-Read state to a uni-directional quantum Hall stripe, which has a periodicity of a few magnetic lengths and survives in the thermodynamic limit.
Topic: AdS/CFT, condensed matter physics, and general relativity
Speaker: Jie REN (Hebrew Univ.)
Time: 14:00pm, Jan. 9 (Tue.), 2018
Venue: Rm. S401, Kavli ITS Meeting Room, UCAS Teaching Building [Map]