Novel Type of Superlattices Based on Gapless Graphene with the Alternating Fermi Velocity

TL;DR

This paper introduces a new type of graphene superlattice created by periodic Fermi surface modulation via striped or grooved substrates, affecting electronic properties and potential device applications.

Contribution

It proposes a model for graphene superlattices with alternating Fermi velocity, analyzing their dispersion relation and energy spectrum using transfer-matrix techniques.

Findings

Derived the dispersion relation for the superlattices.

Calculated the energy spectrum of the proposed structures.

Provided qualitative analysis of current-voltage characteristics.

Abstract

We study a novel type of graphene-based superlattices formed owing to a periodic modulation of the Fermi surface. Such a modulation is possible for graphene deposited on a striped substrate made of materials with substantially different values of the dc permittivity. Similar superlattices appear also in graphene sheets applied over substrates with a periodic array of parallel grooves. We suggest a model describing such superlattices. Using the transfer-matrix technique, we determine the dispersion relation and calculate the energy spectrum of these superlattices. We also analyze at a qualitative level the current--voltage characteristics of the system under study.