Cross-polarized and stable second harmonic generation from monocrystalline copper.

ABSTRACT: Second-harmonic generation (SHG) is a powerful surface-specific probe for centrosymmetric materials, with broad relevance to energy and biological interfaces. Plasmonic nanomaterials have been extensively utilized to amplify this nonlinear response. Yet, material instability has constrained most studies to gold, despite the significance of plasmonic metals such as copper for catalysis. Here, we demonstrate stable and anisotropic SHG from monocrystalline copper, overcoming long-standing challenges associated with surface degradation. By leveraging an on-substrate synthesis approach that yields atomically flat and oxidation-resistant Cu microflakes, we enable reliable SHG measurements and reveal a strong cross-polarized response with C _3v surface symmetry. The SHG si

SUBMITTER: Dayi EN 

PROVIDER: S-EPMC12714057 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature