Large-area, freestanding single-crystal gold of single nanometer thickness

Abstract

Two-dimensional single-crystal metals are highly sought after for next-generation technologies. Here, we report large-area (>10^4 μm2), single-crystal two-dimensional gold with thicknesses down to a single-nanometer level, employing an atomic-level-precision chemical etching approach. The ultrathin thickness and single-crystal quality endow two-dimensional gold with unique properties including significantly quantum-confinement-augmented optical nonlinearity, low sheet resistance, high transparency and excellent mechanical flexibility. By patterning the two-dimensional gold into nanoribbon arrays, extremely-confined near-infrared plasmonic resonances are further demonstrated with quality factors up to 5. The freestanding nature of two-dimensional gold allows its straightforward manipulation and transfer-printing for integration with other structures. The developed two-dimensional gold provides an emerging platform for fundamental studies in various disciplines and opens up new opportunities for applications in high-performance ultrathin optoelectronic, photonic and quantum devices.

References in corpus (6)

• Mid-Infrared Plasmonic Biosensing with Graphene
• Atomically flat single-crystalline gold nanostructures for plasmonic nanocircuitry
• Optical and Structural Properties of Ultra-thin Gold Films
• Plasmonics in Atomically-Thin Crystalline Silver Films
• Atomically smooth single-crystalline platform for low-loss plasmonic nanocavities
• Nonclassical optical properties of mesoscopic gold

Cited by in corpus (5)

• Roadmap for Photonics with 2D Materials
• Roadmap on Nonlocality in Photonic Materials and Metamaterials
• Active control of excitonic strong coupling and electroluminescence in electrically driven plasmonic nanocavities
• On-chip Single-crystal Plasmonic Optoelectronics for Efficient Hot Carrier Collection and Photovoltage Detection
• Goos-Hänchen effect singularities in transdimensional plasmonic films