Electronic states in 2D materials can exhibit pseudospin degrees of freedom, which allow for unique carrier-field interaction scenarios. Here, we investigate ultrafast sublattice pseudospin relaxation in graphene by means of polarization-resolved photoluminescence spectroscopy. Comparison with microscopic Boltzmann simulations allows to determine a lifetime of the optically aligned pseudospin distribution of 12±2fs. This experimental approach extends the toolbox of graphene pseudospintronics, providing novel means to investigate pseudospin dynamics in active devices or under external fields.
@article{arxiv.1702.00962,
title = {Polarized photoluminescence clocks ultrafast pseudospin relaxation in graphene},
author = {Thomas Danz and Andreas Neff and John H. Gaida and Reiner Bormann and Claus Ropers and Sascha Schäfer},
journal= {arXiv preprint arXiv:1702.00962},
year = {2017}
}