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arXiv · 2601.14178

Anomalous Tip-Sample Distance Behavior on the Tip-Enhanced Raman Spectroscopy of Graphene in Ambient Conditions

André G. Pereira·Raul Corrêa·Bianca Carneiro·Cassiano Rabelo·Thiago L. Vasconcelos·Vitor Monken·Luiz Gustavo Cançado·Ado Jorio
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Abstract

Tip-Enhanced Raman Spectroscopy (TERS) combines Raman spectroscopy with scanning probe microscopy to overcome the spatial resolution limitation imposed by light diffraction, offering a primary optical technique for the comprehensive study of two-dimensional (2D) materials. In this work, we investigate an anomalous decay profile of the TERS intensity of the graphene 2D band as the tip-sample separation changes, observations enabled by high TERS efficiency and accuracy in tip-approach and tip-retract procedures. The anomalous results can be properly described by the addition of an ad hoc deformation to the effective tip-sample distance, rationalized here as due to the presence of a liquid meniscus formed via capillary forces.

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André G. Pereira, Raul Corrêa, Bianca Carneiro, Cassiano Rabelo, Thiago L. Vasconcelos, Vitor Monken, Luiz Gustavo Cançado, Ado Jorio. 2026-01-20. Anomalous Tip-Sample Distance Behavior on the Tip-Enhanced Raman Spectroscopy of Graphene in Ambient Conditions. https://doi.org/10.1063/5.0317020

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