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arXiv · 2608.18885

Spectral Fingerprints of Resonant Defect Scattering by Substitutional Mn in Graphene

Ahmed Samir Lotfy·Zviadi Zarkua·Renan Villarreal·Rikkie Joris·Muhammad Saad·Koen van Stiphout·Karina Landivar·Steven Brems·Giovanni Di Santo·Aleksandr Seliverstov·Simona Achilli·Luca Petaccia·Lino M. C. Pereira
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Abstract

Using substitutional Mn in graphene/Cu(111) as a model point defect, we combine scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES) to test the predicted fingerprints of resonant scattering. As the Mn concentration increases to 0.44%, the Dirac point stretching reaches 0.52 eV, while momentum broadening remains energy independent. These spectral fingerprints classify substitutional Mn as a strong resonant scatterer and establish the combination of STM and ARPES as a powerful approach to identify and characterize resonant disorder in graphene.

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Ahmed Samir Lotfy, Zviadi Zarkua, Renan Villarreal, Rikkie Joris, Muhammad Saad, Koen van Stiphout, Karina Landivar, Steven Brems, Giovanni Di Santo, Aleksandr Seliverstov, Simona Achilli, Luca Petaccia, Lino M. C. Pereira. 2026-08-19. Spectral Fingerprints of Resonant Defect Scattering by Substitutional Mn in Graphene. https://arxiv.org/abs/2608.18885

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