Abstract

By rational design and parameter engineering of the TiO₂-Pt core-satellite construction, visible light absorption in small Pt nanoparticles (NPs) can be enhanced by nearly 100 times. The TiO₂ microsphere support works as the optical antenna, giving rise to superior performance compared to conventional plasmonic nanoantennas. A crucial step is to bury the Pt NPs completely in the high refractive index TiO₂ microsphere, because light absorption in the Pt NP approximately scales with the fourth power of the refractive index of its surrounding media. The proposed evaluation factor for light absorption enhancement in the Pt NPs at different positions is proved to be valid and useful. The physics modeling of the buried Pt NPs corresponds to the general case in practice where the surface of the TiO₂ microsphere is naturally rough or a thin TiO₂ coating is subsequently added. These results offer new avenues for directly transforming dielectric supported nonplasmonic catalytic transition metals into visible light photocatalysts.

© 2022 Optica Publishing Group

High refractive index dielectric coating on plasmonic nanoantennas for strong visible light absorption in small transition metal nanoparticle reactors

Qiuyan Wang, Liren Deng, Guo Zhou, Yukun Zhu, Runqi Han, and Yu Huang
Opt. Lett. 48(11) 3011-3014 (2023)

Nanovibration detection based on a microsphere

Chunlei Jiang, Weicheng Wang, Bing Yan, Peng Chen, Kaichuan Xu, Yu Sun, Zhicheng Cong, Taiji Dong, Yekun Zhou, Zengbo Wang, and Xiufang Wang
Opt. Lett. 47(17) 4560-4563 (2022)

On-chip asymmetric beam-steering for broadband visible light

Yangyang Shi, Rui Yang, Chenjie Dai, Chengwei Wan, and Zhongyang Li
Opt. Lett. 47(2) 369-372 (2022)

Unidirectional invisibility in a PT-symmetric structure designed by topology optimization

Kei Matsushima, Yuki Noguchi, and Takayuki Yamada
Opt. Lett. 47(13) 3315-3318 (2022)

To generate a photonic nanojet outside a high refractive index microsphere illuminated by a Gaussian beam

Vlatko Gašparić, Thomas G. Mayerhöfer, David Zopf, Davor Ristić, Jürgen Popp, and Mile Ivanda
Opt. Lett. 47(10) 2534-2537 (2022)