posted on 2022-01-13, 18:13authored byJunjun Shi, Xiaobo He, Wen Chen, Yang Li, Meng Kang, Yangjian Cai, Hongxing Xu
On-chip
nanoscale optical platforms capable of efficient second
harmonic generation (SHG) are highly desired for optical sensing,
subwavelength coherent sources, and quantum photonic devices. Here,
we develop a remotely excited dual cavity resonance scheme to achieve
significantly enhanced SHG in a CdSe nanobelt on Au film hybrid waveguide
system. The SHG emission with superior efficiency originates from
counter-propagating plasmonic modes interference in a horizontal Fabry-Pérot
(FP) cavity enabled by remote excitation of propagating surface plasmons,
which is further enhanced through a vertical FP cavity. With this
effective cooperation of hybrid plasmon modes and FP cavity modes,
2 orders of magnitude enhancement of the conversion efficiency (3.5
× 10–4 W–1) is achieved compared
to the off-resonance case. Our design provides new insight into the
development of a multifunctional hybrid plasmonic device toward on-chip
nonlinear nanophotonic applications.