Multichannel pseudo fermion approach to the Kondo lattice model
Jiangfan Wang1, Yung-Yeh Chang1*, Chung-Hou Chung1
1Electrophysics, National Chiao Tung University, Hsinchu, Taiwan
* Presenter:Yung-Yeh Chang,
We establish a novel theoretical framework to study the quantum phases and phase transitions of a two-dimensional Kondo Heisenberg lattice model based on dynamical large-Napproach to the multichannel pseudo-fermion representation of the model with Sp(N) Χ SU(K) symmetry with N and K being the number of spin flavors and Kondo-screening channels, respectively. This approach captures the heavy electron Fermi-liquid state when SU(K) symmetry is broken with Kondo hybridization in terms of Bose-condensed holons, and a metallic spin-liquid state with gapped fermionic spinons when the antiferromagnetic coupling dominates. A self-consistent Green’s function method is used. The global phase diagram and the thermodynamic properties of the spin liquid state share close resemblance to CePdAl, a heavy-fermion systems with magnetic frustration

Keywords: Quantum phase transition, Kondo lattice, Heavy fermion material, Spin liquid, Pseudofermion