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The realization of air-stable two-dimensional (2D) metals confined at the interface between graphene and SiC has attracted significant attention owing to their distinct properties compared to their bulk counterparts. In this work, we identify two distinct structural phases in a monolayer silver intercalated between graphene and SiC: (i) a moiré pattern arising from the lattice mismatch between graphene and monolayer silver and (ii) a striped reconstruction formed through the interaction with the underlying SiC. Using cryogenic scanning tunneling microscopy combined with density functional theory, we elucidate the origin of the silver striped reconstruction. Driven by the competition between the silver-SiC and the silver-silver interactions within a monolayer, the silver atoms form a one-dimensional Frenkel-Kontorova domain, in which an $(n+1)\times \surd 3$silver supercell accommodates an $n\times \surd 3$supercell $(n=20)$of the underlying SiC, which partially relieves tensile strain, otherwise imposed by ideal epitaxy. The strain-induced reconstruction creates a long-range modulation of 2D silver electronic density, giving rise to an electronic state at $\sim 0.75\mathrm{eV}$above the Fermi level in the transition regions between different silver-SiC registries. These findings uncover the important interplay between the structural and electronic properties of intercalated 2D metals and the underlying SiC substrate, providing new insights into substrate-mediated reconstruction and electronic modulation at confined interfaces. 

Abstract Tomonaga-Luttinger liquid (TLL) behavior in one-dimensional systems has been predicted and shown to occur at semiconductor-to-metal transitions within two-dimensional materials. Reports of one-dimensional defects hosting a Fermi liquid or a TLL have suggested a dependence on the underlying substrate, however, unveiling the physical details of electronic contributions from the substrate require cross-correlative investigation. Here, we study TLL formation within defectively engineered WS₂atop graphene, where band structure and the atomic environment is visualized with nano angle-resolved photoelectron spectroscopy, scanning tunneling microscopy and spectroscopy, and non-contact atomic force microscopy. Correlations between the local density of states and electronic band dispersion elucidated the electron transfer from graphene into a TLL hosted by one-dimensional metal (1DM) defects. It appears that the vertical heterostructure with graphene and the induced charge transfer from graphene into the 1DM is critical for the formation of a TLL. 

Substitutionally doped transition metal dichalcogenides (TMDs) are essential for advancing TMD‐based field effect transistors, sensors, and quantum photonic devices. However, the impact of local dopant concentrations and dopant–dopant interactions on charge doping and defect formation within TMDs remains underexplored. Here, a breakthrough understanding of the influence of rhenium (Re) concentration is presented on charge doping and defect formation in MoS₂monolayers grown by metal–organic chemical vapor deposition (MOCVD). It is shown that Re‐MoS₂films exhibit reduced sulfur‐site defects, consistent with prior reports. However, as the Re concentration approaches ⪆2 atom%, significant clustering of Re in the MoS₂is observed. Ab Initio calculations indicate that the transition from isolated Re atoms to Re clusters increases the ionization energy of Re dopants, thereby reducing Re‐doping efficacy. Using photoluminescence (PL) spectroscopy, it is shown that Re dopant clustering creates defect states that trap photogenerated excitons within the MoS₂lattice, resulting in broad sub‐gap emission. These results provide critical insights into how the local concentration of metal dopants influences carrier density, defect formation, and exciton recombination in TMDs, offering a novel framework for designing future TMD‐based devices with improved electronic and photonic properties.