Open AccessGe2Sb2Te5-based nanocavity metasurface for enhancement of third harmonic generation
Author(s) -
Yang Li,
Xuecai Zhang,
Yi Tang,
Wenfeng Cai,
Kuan Liu,
Ningbin Mao,
Kingfai Li,
Junhong Deng,
Yan Jun Liu,
Tun Cao,
Guixin Li
Publication year - 2021
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/ac3317
Subject(s) - physics , nanophotonics , femtosecond , ultrashort pulse , optoelectronics , nonlinear optics , laser , nonlinear system , optics , planar , second harmonic generation , harmonic , quantum mechanics , computer graphics (images) , computer science
The third-order nonlinear processes in nanophotonic devices may have great potentials for developing ultra-compact nonlinear optical sources, ultrafast optical switches and modulators, etc. It is known that the performance of the nonlinear nanophotonic devices strongly relies on the optical resonances and the selection of appropriate nonlinear materials. Here, we demonstrate that the third harmonic generations (THG) can be greatly enhanced at subwavelength scale by incorporating α-Ge 2 Sb 2 Te 5 (α-GST) into the nanocavity metasurface. Under pumping of a near-infrared femtosecond laser, the THG from the nanocavity metasurface is ∼50 times stronger than that from the bare GST planar film. In addition, the nanocavity metasurface also provides a powerful platform for characterizing the third-order nonlinear susceptibility of the active medium in the cavity. We expect that the GST-based nanocavity metasurface could open new routes for achieving high efficiency nonlinear nanophotonic devices.