Nitride Wide-Bandgap Semiconductors for UV Nonlinear Optics

Abstract

Nitride wide-bandgap semiconductors possess a wide tunable energy bandgap and abundant coordination anionic groups. This suggests their potential to display nonlinear optical (NLO) properties in the UV wavelength spectrum. This paper reports recent progress and material discoveries in exploring UV NLO structures using nitrides. The study emphasizes their underlying structure–property correlations in order to provide a summary of the potential performance and application value of important nitride NLO crystals. Additionally, the text underscores the benefits of nitrides in terms of optical transparency, second-harmonic-generation effects, and the birefringent phase matching the output wavelength limits, while addressing current issues in terms of theoretical outlook and experimental exploration.

Wide-Band Gap Binary Semiconductor P3N5 with Highly Anisotropic Optical Linearity and Nonlinearity

“…Wide-band gap binary semiconductors, such as SiC, GaN, AlN, Ga 2 O 3 , and Si 3 N 4 , have important applications in high-voltage devices, solar-blind photodetectors, and waveguide devices. − Their attributes like high optical transparency, tunable electronic conductivity, and controllable carrier concentration make them attractive in consumer electronics, renewable energy, and transportation. − These materials have wide energy band gaps ( E g ), which make them suitable for optoelectronic applications and photophysical studies in the 100–400 nm ultraviolet (UV) spectral range . Nitrides, in particular, exhibit potential for UV nonlinear optical (NLO) frequency conversion, such as second harmonic generation (SHG), due to their tunable E g and extensive coordination anionic motifs . Anionic groups with different coordination, such as tetrahedra, chain, and other kinds of groups, can produce different macroscopic optical properties, offering great potential for exploring new high-performance NLO crystals …”

“…10 Nitrides, in particular, exhibit potential for UV nonlinear optical (NLO) frequency conversion, such as second harmonic generation (SHG), due to their tunable E g and extensive coordination anionic motifs. 11 Anionic groups with different coordination, such as tetrahedra, chain, and other kinds of groups, can produce different macroscopic optical properties, offering great potential for exploring new high-performance NLO crystals. 12 However, effective UV NLO frequency conversion requires more than just band gap and SHG effect.…”