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DOE OSTI · 1843664

Reshaped Weyl fermionic dispersions driven by Coulomb interactions in MoTe 2

Kang, Seoung-Hun·Jeon, Sangjun·Kim, Hyun-Jung·Ko, Wonhee·Cho, Suyeon·Kang, Se Hwang·Kim, Sung Wng·Yang, Heejun·Kim, Hyo Won·Son, Young-Woo
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Abstract

In this work, we report the direct evidence of impacts of the Coulomb interaction in a prototypical Weyl semimetal, MoTe 2 , that alter its bare bands in a wide range of energy and momentum. Our quasiparticle interference patterns measured using scanning tunneling microscopy are shown to match the joint density of states of quasiparticle energy bands including momentum-dependent self-energy corrections, while electronic energy bands based on the other simpler local approximations of the Coulomb interaction fail to explain neither the correct number of quasiparticle pockets nor the shape of their dispersions observed in our spectrum. With this, we predict a transition between type-I and type-II Weyl fermions with doping and resolve its disparate quantum oscillation experiments, thus highlighting the critical roles of Coulomb interactions in layered Weyl semimetals.

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Kang, Seoung-Hun, Jeon, Sangjun, Kim, Hyun-Jung, Ko, Wonhee, Cho, Suyeon, Kang, Se Hwang, Kim, Sung Wng, Yang, Heejun, Kim, Hyo Won, Son, Young-Woo. 2022-01-31. Reshaped Weyl fermionic dispersions driven by Coulomb interactions in MoTe 2. https://doi.org/10.1103/physrevb.105.045143

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