2011/02/28 by Zhihao Lan, Z. Lan, Nathan Goldman +7 · 3 citations
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Dirac (video compression format) #Dirac fermion #Fermion #Hamiltonian (control theory) #Helicity #Massless particle #Neutrino #Physics #Quantum and electron transport phenomena #Quantum mechanics #Spin (aerodynamics) #Topological Materials and Phenomena #cond-mat.quant-gas #hep-lat
paper · pdf · doi:10.1103/physrevb.84.165115
published as Phys. Rev. B 84, 165115 (2011) · replaced with published version; title changed; typos corrected; references updated
openalex publication_date 2011/10/14 · arxiv created 2011/12/31 · arxiv updated 2012/01/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Dirac-Weyl fermions are massless relativistic particles with a well-defined helicity which arise in the context of high-energy physics. Here we propose a quantum simulation of these paradigmatic fermions using multicomponent ultracold atoms in a two-dimensional square optical lattice. We find that laser-assisted spin-dependent hopping, specifically tuned to the (2s+1)-dimensional representations of the \mathfraksu(2) Lie algebra, directly leads to a regime where the emerging massless excitations correspond to Dirac-Weyl fermions with arbitrary pseudospin s. We show that this platform hosts two different phases: a semimetallic phase that occurs for half-integer s, and a metallic phase that contains a flat zero-energy band at integer s. These phases host a variety of interesting effects, such as a very rich anomalous quantum Hall effect and a remarkable multirefringent Klein tunneling. In addition, we show that these effects are directly related to the number of underlying Dirac-Weyl species and zero modes.