Network model for periodically strained graphene

The long-wavelength physics of monolayer graphene in the presence periodic strain fields has a natural chiral scattering network description. When field varies slowly compared to lattice and effective magnetic length induced valley pseudomagnetic field, low-energy can be understood terms valley-polarized percolating domain-wall modes. Inspired by recent experiment, we consider with threefold rotation mirror symmetries but without twofold symmetry, resulting system connectivity oriented kagome network. Scattering processes this are captured symmetry-constrained phenomenological $S$ matrix. We analyze phase diagram show that bulk strained qualitatively when account for percolation transition at charge neutrality. also discuss limitations approach properly boundary physics.