Confined monolayer Ag as a large gap 2D semiconductor and its momentum resolved excited states

Abstract

2D materials have intriguing quantum phenomena that are distinctively different from their bulk counterparts. Recently, epitaxially synthesized wafer-scale 2D metals, composed of elemental atoms, are attracting attention not only for their potential applications but also for exotic quantum effects such as superconductivity. By mapping momentum-resolved electronic states using time-resolved and angle-resolved photoemission spectroscopy (ARPES), we reveal that monolayer Ag confined between bilayer graphene and SiC is a large gap (> 1 eV) 2D semiconductor, consistent with GW-corrected density functional theory. The measured valence band dispersion matches the DFT-GW quasiparticle band. However, the conduction band dispersion shows an anomalously large effective mass of 2.4 m0. Possible mechanisms for this large enhancement in the apparent mass are discussed.

References in corpus (4)

• Observation of giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor
• Truncation of Periodic Image Interactions for Confined Systems
• Dynamic Screening and Low Energy Collective Modes in Bilayer Graphene
• Surface charge-transfer doping a quantum-confined silver monolayer beneath epitaxial graphene

Cited by in corpus (4)

• Monolayer Magnetic Metal with Scalable Conductivity
• Point defects and their dynamic behaviors in silver monolayer intercalated between graphene and SiC
• Ultra-Confinement of Polaritons in Single Atomic Layer Ag Photonic Quantum Dots
• Defect-Mediated Phase Engineering of 2D Ag at the Graphene/SiC Interface