Nonlinear Optical Microscopy of Semiconductor Metal-Nanocavities
Abstract
We use second and third harmonic generation microscopy to investigate the nonlinear optical response of GaAs nanocavities embedded in a gold film and compare them to bare GaAs nanocavities. Our results reveal that the surrounding metallic environment significantly modifies both the intensity and spatial distribution of the nonlinear signals. When the harmonic wavelength is spectrally detuned from the nanocavity resonance, the effects due to the metallic environment start suppressing the SHG contrast. Numerical simulations confirm that at a 1060 nm pump wavelength, the SHG produced at 530 nm is suppressed due to the dominant plasmonic response of gold. Meanwhile, the THG produced at 353 nm, which coincides with the nanocavity resonance, enables high contrast imaging. Furthermore, by shifting the pump to 710 nm, aligning SHG at 356 nm with the nanocavity resonance, we recover strong SHG contrast, demonstrating a pathway to enhanced imaging of metal-semiconductor heterostructures.
Keywords
Cite
@article{arxiv.2504.03402,
title = {Nonlinear Optical Microscopy of Semiconductor Metal-Nanocavities},
author = {Riya Varghese and Shambhavee Annurakshita and Yaraslau Tamashevich and Abhiroop Chellu and Subhajit Bej and Heikki Rekola and Jari Lyytikainen and Hanna Wahl and Matias Schildt and Ali Panahpour and Tapio Niemi and Marco Ornigotti and Petri Karvinen and Mircea Guina and Teemu Hakkarainen and Mikko J. Huttunen},
journal= {arXiv preprint arXiv:2504.03402},
year = {2025}
}