Effects of a uniform magnetic field on twisted graphene nanoribbons

• URL: http://arxiv.org/abs/2303.04645v1
• Date: Wed, 8 Mar 2023 15:06:00 GMT
• Title: Effects of a uniform magnetic field on twisted graphene nanoribbons
• Authors: Camila C. Soares, Angel E. Obispo, Andr\'es G. Jir\'on Vicente, Luis B. Castro
• Abstract summary: relativistic quantum motion of massless fermions in a helicoidal graphene nanoribbon under the influence of a uniform magnetic field is investigated. It is verified that the presence of $B$ produces a constant minimum value of local density of state on the axis of helicoid.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: In the present work, the relativistic quantum motion of massless fermions in a helicoidal graphene nanoribbon under the influence of a uniform magnetic field is investigated. Considering a uniform magnetic field ($B$) aligned along the axis of helicoid, this problem is explored in the context of Dirac equation in a curved space-time. As this system does not support exact solutions due to considered background, the bound-state solutions and local density of state (LDOS) are obtained numerically by means of the Numerov method. The combined effects of width of the nanoribbon ($D$), length of ribbon ($L$), twist parameter ($\omega$) and $B$ on the equations of motion and local density of states (LDOS) are analyzed and discussed. It is verified that the presence of $B$ produces a constant minimum value of local density of state on the axis of helicoid, which is possible only for values large enough of $\omega$, in contrast to the case for $B=0$ already studied in the literature.

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