Pseudo-magnetic field distribution and pseudo-Landau levels in suspended   graphene flakes
  Combining the tight-binding approximation and linear elasticity theory for a planar membrane, we investigate stretching of a graphene flake assuming that two opposite edges of the sample are clamped by the contacts. We show that, depending on the aspect ratio of the flake and its orientation, gapped states may form in the membrane in the vicinity of the contacts. This gap in the pre-contact region should be biggest for the armchair orientation of the flake and width to length ratio of around 1. 
M. Mucha-Kruczynski and V.I. Fal'ko
cond-mat.mes-hall