Second harmonic generation from aluminum plasmonic nanocavities: from scanning to imaging

Tchiya Zar, Alon Krause, Omer Shavit, Hannah Aharon, Racheli Ron, Martin Oheim, Adi Salomon

Research output: Contribution to journalArticlepeer-review

Abstract

Metamaterials and plasmonic structures made from aluminum (Al) have attracted significant interest due to their low cost, long-term stability, and the relative abundance of aluminum compared to the rare metals. Also, aluminum displays distinct dielectric properties allowing for the excitation of surface plasmons in the ultraviolet region with minimal non-radiative losses. Despite these clear advantages, most of the research has been focused on either gold or silver, probably due to difficulties in forming smooth thin films of aluminum. In the present work, we detect and characterize second harmonic generation (SHG) in the optical regime, emanating from triangular hole arrays milled into thin aluminum films in reflection mode, at normal incidence. We report intense nonlinear responses, year-long stability, and overall superior performances with respect to gold. The robustness of the Al structures and high reproducibility of the measured SHG responses allowed us to investigate changes in the directional emission upon tiny modifications in the structure's symmetry. We also demonstrate large-field instantaneous SHG imaging over areas containing several hole arrays using a recent, non-linear single-spinning disk microscope. Such high spatio-temporal resolution imaging has important applications, e.g., when studying chemical transformations occurring at electrode surfaces during charging and discharging cycles, as well as ageing.

Original languageEnglish
Pages (from-to)18915-18925
Number of pages11
JournalPhysical Chemistry Chemical Physics
Volume25
Issue number28
DOIs
StatePublished - 19 Jul 2023

Bibliographical note

Publisher Copyright:
© 2023 The Royal Society of Chemistry.

Fingerprint

Dive into the research topics of 'Second harmonic generation from aluminum plasmonic nanocavities: from scanning to imaging'. Together they form a unique fingerprint.

Cite this