We show how the trigonal warping effect in doped graphene can be used to produce fully valley polarized currents. We propose a device that acts both as a beam splitter and a collimator of these electronic currents. The result is demonstrated trough an optical analogy using two dimensional photonic crystals.
@article{arxiv.0710.1004,
title = {Valley polarized electronic beam splitting in graphene},
author = {J. L. Garcia-Pomar and A. Cortijo and M. Nieto-Vesperinas},
journal= {arXiv preprint arXiv:0710.1004},
year = {2007}
}