Twisted Graphene Nanoribbons: Electronic and Mechanical Properties

Twisted graphene nanoribbons represent a rapidly advancing class of low-dimensional materials in which the characteristic one-atom-thick ribbon of carbon honeycomb lattice is subjected to a defined torsional deformation along its length. By introducing a controlled twist angle between ribbon segments or layers, the electronic band structure can be tuned to open a bandgap, localise edge states and even induce spin polarisation. Mechanically, the act of twisting modifies bending stiffness, torsional rigidity and phonon transport, offering routes to enhanced flexibility and thermal management in nanoscale devices. These intertwined electronic and mechanical responses underpin prospects for twist-engineered nanoelectronics, spintronic interconnects and flexible thermal interfaces, while fundamental studies continue to elucidate the interplay between atomic registry, interlayer coupling and defect-mediated scattering in twisted architectures.

Research from Nature Portfolio

Recent studies have shown that epitaxially grown graphene nanoribbons on silicon carbide substrates, when subjected to a small rotational misalignment between adjacent ribbon segments, develop an intrinsic bandgap of up to a few hundred millielectronvolts. Spectroscopic and transport measurements reveal nonlinear current–voltage characteristics and high carrier mobility maintained at low temperatures, demonstrating that twist-induced interlayer coupling can be harnessed for semiconducting behaviour in otherwise gapless graphene. In parallel, investigations of nanoribbons bearing local structural distortions—analogous to torsional defects—have uncovered pronounced phononic Fano resonances. These arise from the interference between discrete vibrational modes localised at the defect sites and propagating phonons, leading to a significant suppression of thermal conductivity, especially at cryogenic temperatures where phonon transport dominates heat flow.

Twisted Graphene Nanoribbons: Electronic and Mechanical Properties publication trend

The graph below shows the total number of articles in twisted graphene nanoribbons: electronic and mechanical properties across all publications each year (not limited to Nature Index journals).

Technical terms

Graphene nanoribbon: A narrow strip of graphene, typically a few nanometres wide, with well-defined edge structure and quantum-confinement effects.

Twist angle: The relative rotational orientation between adjacent segments or layers in a nanoribbon, usually measured in degrees.

Bandgap: The energy difference between the valence band and conduction band in a material, determining its semiconducting or metallic character.

Phonon: A quantised lattice vibration that carries thermal energy through a crystal.

Torsional rigidity: A measure of a ribbon’s resistance to twisting deformation, related to its mechanical stiffness under torque.

References

1. Observation of the intrinsic bandgap behaviour in as-grown epitaxial twisted graphene. Nature Communications (2015).
2. Phononic Fano resonances in graphene nanoribbons with local defects. Scientific Reports (2017).
3. Effect of Tensile Strain on Thermal Conductivity in Monolayer Graphene Nanoribbons: A Molecular Dynamics Study. Sensors (2013).