▎ 摘　　要

NOVELTY - Plasmonic or electronically resonant material comprises a substrate, an epitaxial growth layer comprising a graphene layer, and an interface layer formed between the graphene layer and the substrate, where the interface layer comprises graphene passivated with intercalant. USE - The plasmonic or electronically resonant material is used in a sensor system for a Raman spectrometer (all claimed). ADVANTAGE - The plasmonic or electronically resonant material exhibits a range of optical properties, including plasmonic or electronic resonance, that enables superior optical (e.g. Raman) detection of molecules. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a sensor system (A), comprising a switch comprising the plasmonic or electronically resonant material, where the interface layer comprises pristine graphene passivated with intercalant, and plasmons are generated in the interface layer when light is incident upon the plasmonic or electronically resonant material, and the incident light couples with the plasmons to form surface plasmon polaritons, and a detector configured to detect the surface plasmon polaritons; (2) a sensor system (B) for Raman spectroscopy, comprising the plasmonic or electronically resonant material, where the light is electromagnetic radiation emitted from a sample due to Raman scattering interactions induced in the sample, and a detector configured to detect the surface plasmon polaritons; (3) a compressed heterostructure plasmonic or electronically resonant material, comprising a first substrate having a graphene layer formed on it, a second substrate, and a metallic species arranged between the graphene layer and the second substrate, where the first substrate and second substrate are compressed under heat and pressure to form a layered heterostructure; (4) a method for forming the plasmonic or electronically resonant material, comprising (a) generating epitaxial growth layers on a substrate, where the epitaxial growth layers comprise a buffer layer adjacent the substrate, where the buffer layer is an electrically inactive layer, and the buffer layer is partially bonded via covalent bonding to the substrate, and a growth layer adjacent the buffer layer, where the growth layer is an electrically active layer, intercalating the buffer layer with intercalant by allowing the intercalant to migrate through defects in the growth layer and into the buffer layer, where the intercalate physically and electronically decouples the buffer layer from the substrate; and (5) a Raman spectrometer comprising a light source configured to generate light that incident upon a sample, a detector configured to detect electromagnetic radiation generated by the sample, the plasmonic or electronically resonant material upon which the sample is placed, where the laser light interacts with the sample, molecules of the sample are excited so that molecular vibrations are generated, an electronic resonance is generated in the interface layer when the molecular vibrations occur, and the molecular vibrations couple with the electronic resonance to enhance the electromagnetic radiation emitted from the sample.