Professor Olexei I. Motrunich
California Institute of Technology

Spinon Fermi sea state as a candidate spin liquid in κ-(ET)Cu₂(CN)₃

Experimental studies of the quasi-two-dimensional organic compound κ-(ET)Cu₂(CN)₃ strongly suggest a spin liquid state in the insulating phase at ambient pressure. This material is modelled as a half-filled triangular lattice Hubbard system close to the Mott transition. A trial wave function study of an appropriate effective spin Hamiltonian with large ring exchanges suggests a spin liquid state with spinon Fermi surface as a good candidate. I will review properties of this state and will further consider the response of this spin liquid to strong magnetic field, with the motivation for looking for direct probes of the spinon Fermi surface.