▎ 摘　　要

We derive a 2+1 dimensional model with unconventional supersymmetry at the boundary of an AdS(4)N-extended supergravity, generalizing previous results. The (unconventional) extended supersymmetry of the boundary model is instrumental in describing, within a top-down approach, the electronic properties of graphene-like 2D materials at the two Dirac points, K and K '. The two valleys correspond to the two independent sectors of the OSp(p vertical bar 2) x OSp(q vertical bar 2) boundary model in the p = q case, which are related by a parity transformation. The Semenoff and Haldane-type masses entering the corresponding Dirac equations are identified with the torsion parameters of the substrate in the model.