How electrons Coulomb repulsion changes Graphene band structure

Rostam Moradian; Poorya Rabibegi

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arXiv · 2111.01712

How electrons Coulomb repulsion changes Graphene band structure

Rostam Moradian·Poorya Rabibegi

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Abstract

How electron-electron Coulomb repulsion modifies electronic band structure is a big change in strongly correlated systems. We introduced a method for calculation of realistic band structure of these systems and eliminating fake states. By using this method we investigated how electrons repulsion renormalizes graphene band structure. Our results show that in the dynamical mean field theory at Coulomb repulsion $u=2.596 t$ a four band semi metal to four bands anti ferro magnetism phase transition starts while due to inter site correlation for four sites, $nc=4$, effective medium super cell approximation it is $u=3.2 t$.

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Rostam Moradian, Poorya Rabibegi. 2021-11-02. How electrons Coulomb repulsion changes Graphene band structure. https://arxiv.org/abs/2111.01712

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