Dirac Fermions in Optical Lattices

Alessio Celi

Emilio Alba, Xavier Fernandez-Gonzalvo, Jordi Mur-Petit +2 more

Ya-Fei Yu, Chuan-Jia Shan, Feng Mei +1 more

Tilman Esslinger

Luca Lepori, Giuseppe Mussardo, Andrea Trombettoni

We propose the experimental realization of (3+1) relativistic Dirac fermions using ultracold atoms in a rotating optical lattice or, alternatively, in a synthetic magnetic field. This approach has the advantage to give mass to the Dirac fermions by coupling the ultracold atoms to a Bragg pulse. A dimensional crossover from (3+1) to (2+1) Dirac fermions can be obtained by varying the anisotropy of the lattice. We also discuss under which conditions the interatomic potentials give rise to relativistically invariant interactions among the Dirac fermions.

Shi-Liang Zhu, Baigeng Wang, L.-M. Duan

We propose an experimental scheme to simulate and observe relativistic Dirac fermions with cold atoms in a hexagonal optical lattice. By controlling the lattice anisotropy, one can realize both massive and massless Dirac fermions and observe the phase transition between them. Through explicit calculations, we show that both the Bragg spectroscopy and the atomic density profile in a trap can be used to demonstrate the Dirac fermions and the associated phase transition.