229 nm far-ultraviolet second harmonic generation in a vertical polarity inverted AlN bilayer channel waveguide
Hiroto Honda, Soshi Umeda, Kanako Shojiki, Hideto Miyake, Shuhei Ichikawa, Jun Tatebayashi, Yasufumi Fujiwara, Kazunori Serita, Hironaru Murakami, Masayoshi Tonouchi, Masahiro Uemukai, Tomoyuki Tanikawa, Ryuji Katayama
Abstract
Abstract Far-UV light sources have attracted much attention for human-safe viral inactivation and bacterial disinfection. Due to large optical nonlinearity and transparency to this wavelength region, AlN is a promising material for compact and low-cost far-UV second harmonic generation (SHG) devices. In this study, a transverse quasi-phase-matched AlN channel waveguide with vertical polarity inversion was designed and fabricated. From wavelength spectra and a pump power dependence of an SH intensity, far-UV SHG via the largest nonlinear optical tensor component d 33 was successfully confirmed under ultrashort pulse laser excitation.