Quantum-mechanical effects in photoluminescence from thin crystalline gold films

This paper investigates quantum-mechanical effects in the luminescence of thin monocrystalline gold flakes. Experimental evidence and first-principles simulations demonstrate a photoluminescence origin (radiative emission from electron/hole recombination) when exciting in the interband regime. Quantum-mechanical effects, observable in flakes up to 40 nm thick, are attributed to the out-of-plane discreteness of the electronic band structure near the Fermi level. A model incorporating photon re-absorption and density-functional theory (DFT) calculations accurately reproduces experimental observations, establishing a unified description of luminescence in gold monocrystalline flakes and enabling its use as a probe of carrier dynamics and light-matter interactions.

Alan R. Bowman, Alvaro Rodríguez Echarri, Fatemeh Kiani, Fadil Iyikanat, Ted V. Tsoulos, Joel D. Cox, Ravishankar Sundararaman, F. Javier García de Abajo, Giulia Tagliabue