Resonant transport and line-type resonances in tilted Dirac cone double-barrier structures

TL;DR

This paper investigates how tilting Dirac cones in graphene-based double-barrier structures influences electron transport, revealing resonance phenomena that could inform future nanoelectronic device design.

Contribution

It introduces a systematic analysis of Dirac fermion transmission in tilted-cone graphene structures, highlighting the impact of cone tilt on resonance behaviors and transport properties.

Findings

Multiple resonance peaks, including line-type resonances, occur within forbidden energy zones.

Resonance positions are highly sensitive to system parameters.

Tilted Dirac cones significantly affect transmission and resonance phenomena.

Abstract

We study the transport properties of Dirac fermions in a graphene-based double-barrier structure composed of two tilted-cone regions separated by a central pristine graphene region. Using the transfer matrix method, we systematically analyze how different cone tilts affect Dirac fermion transmission. In reciprocal space, at fixed energy, the Dirac cones of distinct regions generate isoenergetic conical surfaces (Fermi surfaces). When these surfaces overlap, their intersections define ``active surfaces'' that enable fermion transmission. In the symmetric double-barrier configuration, coupling between the barriers and the central well gives rise to multiple resonance peaks, including line-type resonances, even within nominally forbidden energy zones. The number and positions of these resonances depend sensitively on the system parameters. These findings provide new insights into the role of Dirac cone tilt in complex junctions and may guide the design of nanoelectronic devices based on two-dimensional tilted-cone materials such as $\alpha$-(BEDT-TTF)$_2$I$_3$ and borophene.