Continuous wave second harmonic generation enabled by quasi-bound-states in the continuum on gallium phosphide metasurfaces
Abstract
Resonant metasurfaces are an attractive platform for enhancing the non-linear optical processes, such as second harmonic generation (SHG), since they can generate very large local electromagnetic fields while relaxing the phase-matching requirements. Here, we take this platform a step closer to the practical applications by demonstrating visible range, continuous wave (CW) SHG. We do so by combining the attractive material properties of gallium phosphide with engineered, high quality-factor photonic modes enabled by bound states in the continuum. For the optimum case, we obtain efficiencies around 5e-5 % W when the system is pumped at 1200 nm wavelength with CW intensities of 1 kW/cm. Moreover, we measure external efficiencies as high as 0.1 % W with pump intensities of only 10 MW/cm for pulsed irradiation. This efficiency is higher than the values previously reported for dielectric metasurfaces, but achieved here with pump intensities that are two orders of magnitude lower.
Keywords
Cite
@article{arxiv.2102.02406,
title = {Continuous wave second harmonic generation enabled by quasi-bound-states in the continuum on gallium phosphide metasurfaces},
author = {Aravind P. Anthur and Haizhong Zhang and Ramon Paniagua-Dominguez and Dmitry Kalashnikov and Son Tung Ha and Tobias Wilhelm Wolfgang Mass and Arseniy I. Kuznetsov and Leonid Krivitsky},
journal= {arXiv preprint arXiv:2102.02406},
year = {2021}
}