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arXiv · 1702.00962

Polarized photoluminescence clocks ultrafast pseudospin relaxation in graphene

Thomas Danz·Andreas Neff·John H. Gaida·Reiner Bormann·Claus Ropers·Sascha Schäfer
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Abstract

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 $12\pm 2\,\text{fs}$. This experimental approach extends the toolbox of graphene pseudospintronics, providing novel means to investigate pseudospin dynamics in active devices or under external fields.

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Thomas Danz, Andreas Neff, John H. Gaida, Reiner Bormann, Claus Ropers, Sascha Schäfer. 2017-02-03. Polarized photoluminescence clocks ultrafast pseudospin relaxation in graphene. https://doi.org/10.1103/physrevb.95.241412

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