Pseudospin, velocity and Berry phase in a bilayer graphene

Adolfas Dargys; Arturas Acus

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arXiv · 1410.2038

Pseudospin, velocity and Berry phase in a bilayer graphene

Adolfas Dargys·Arturas Acus

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Abstract

Hamiltonian and eigenstate problem is formulated for a bilayer graphene in terms of Clifford's geometric algebra \textit{Cl}$_{3,1}$. It is shown that such approach allows to perform analytical calculations in a simple way if geometrical algebra rotors are used. The measured quantities are express through spectrum and rotation half-angle of the pseudospin that appears in geometric algebra rotors. Properties of free charge carriers -- pseudospin, velocity and Berry phase -- in a bilayer graphene are investigated in the presence of the external voltage applied between the two layers.

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Adolfas Dargys, Arturas Acus. 2014-10-08. Pseudospin, velocity and Berry phase in a bilayer graphene. https://arxiv.org/abs/1410.2038

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