Integration of Er³⁺-emitters in silicon-on-insulator nanodisks metasurface

Erbium (Er³⁺) emitters are relevant for optical applications due to their narrow emission line directly in the telecom C-band due to the ⁴I13/2 → ⁴I15/2 transition at 1.54 $μ$m. Additionally they are promising candidates for future quantum technologies when embedded in thin-film silicon-on-insulator (SOI) to achieve fabrication scalability and CMOS compatibility. In this paper we integrate Er³⁺ emitters in SOI metasurfaces made of closely spaced array of nanodisks, to study their spontaneous emission via room and cryogenic temperature confocal microscopy, off-resonance and in-resonance photoluminescence excitation at room temperature and time resolved spectroscopy. This work demonstrates the possibility to adopt CMOS-compatible and fabrication scalable metasurfaces for controlling and improving the collection efficiency of the spontaneous emission from the Er³⁺ transition in SOI and could be adopted in similar technologically advanced materials.