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arXiv · 2503.17240

Graphene Straintronics by Molecular Trapping

Pawan Kumar Srivastava·Vedanki Khandelwal·Ramesh Reddy·Kartick Tarafder·Subhasis Ghosh
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Abstract

Here, we report on controlling strain in graphene by trapping molecules at the graphene-substrate interface, leveraging molecular dipole moments. Spectroscopic and transport measurements show that strain correlates with the dipole moments of trapped molecules, with a dipole range of 1.5 D to 4.9 D resulting in a 50-fold increase in strain and a substantial rise in the residual carrier density. This has been possible by charge transfer between graphene and trapped molecules, altering the C=C bond length, and causing biaxial strain. First-principles density functional theory calculations confirm a consistent dependence of bending height on molecular dipole moments.

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Pawan Kumar Srivastava, Vedanki Khandelwal, Ramesh Reddy, Kartick Tarafder, Subhasis Ghosh. 2025-03-21. Graphene Straintronics by Molecular Trapping. https://arxiv.org/abs/2503.17240

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