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Regardless of the widely accepted opinion that there is no Raman signal from single-layer graphene when it is strongly bonded to a metal surface, we present Raman spectra of a graphene monolayer on Ni(111) and Co(0001) substrates. The high binding energy of carbon to these surfaces allows formation of lattice-matched (1 × 1) structures where graphene is significantly stretched. This is reflected in a record-breaking shift of the Raman G band by more than 100 cm relative to the case of freestanding graphene. Using electron diffraction and photoemission spectroscopy, we explore the aforementioned systems together with polycrystalline graphene on Co and analyze possible intercalation of oxygen at ambient conditions. The results obtained are fully supported by Raman spectroscopy. Performing a theoretical investigation of the phonon dispersions of freestanding graphene and stretched graphene on the strongly interacting Co surface, we explain the main features of the Raman spectra. Our results create a reliable platform for application of Raman spectroscopy in diagnostics of chemisorbed graphene and related materials.

Herein, the formation of Au nanoclusters on nitridized GaAs(001) surface is described, as well as the structure diagnostics and spectroscopic studies which reveal a strong anisotropy of the plasmons localized on the clusters. Principal aspects of the work are the following. Technologically, structures of Au/N/GaAs are fabricated with a monolayer of nitrogen atoms chemisorbed preliminary onto GaAs substrate to prevent its reaction with subsequently deposited Au film. Annealing of the structures Au/N/GaAs results in the appearance of anisotropic nanoclusters of chemically clean gold on GaAs surface. Experimentally, the existence of in‐surface anisotropy of Au clusters is verified with the atomic force microscopy and it is investigated with the resonant optical spectroscopies of anisotropy reflectance and polarized reflection. All the methods are applied jointly for the detailed study of anisotropic plasmons revealed in gold nanocluster arrays. Theoretically, the plasmon‐conditioned features observed in optical polarized spectra are interpreted using an optical model of in‐surface anisotropic plasmons in Au nanospheroids. As a result, the macroscopic anisotropy and orientation of gold nanoclusters and their plasmons relative to the crystallographic axes of GaAs substrate are unambiguously established and reliably specified.

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