# Winding Vector: How to Annihilate Two Dirac Points with the Same Charge.

@article{Montambaux2018WindingVH,
title={Winding Vector: How to Annihilate Two Dirac Points with the Same Charge.},
author={G. Montambaux and Lih-King Lim and J N Fuchs and Fr{\'e}d{\'e}ric Pi{\'e}chon},
journal={Physical review letters},
year={2018},
volume={121 25},
pages={
256402
}
}
The merging or emergence of a pair of Dirac points may be classified according to whether the winding numbers which characterize them are opposite (+- scenario) or identical (++ scenario). From the touching point between two parabolic bands (one of them can be flat), two Dirac points with the same winding number emerge under appropriate distortion (interaction, etc.), following the ++ scenario. Under further distortion, these Dirac points merge following the +- scenario, that is corresponding…

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