Bistable Mie Nanopaticle based Super-Resolution Microscopy.

Yen Te-Hsin^1*, Yu-Chien Chen¹, Jhih-Jia Chen¹, Kentaro Nishida¹, Junichi Takahara², Shi-Wei Chu^1,3,4

¹Department of Physics, National Taiwan University, Taipei, Taiwan
²Graduate School of Engineering, Osaka University, Osaka, Taiwan
³Molecular Research Center, National Taiwan Unviersity, Taipei, Taiwan
⁴Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan

* Presenter:Yen Te-Hsin, email:tedddy78@gmail.com

Optical nonlinearity has long been used to boost the resolving power of optical microscopy. Several studies have combined super-resolution microscopy and nonlinearity of up-conversion particles, metal and dielectric nanoparticles to achieve resolution on the scale of sub hundred nanometers. These studies have concluded that the slope of nonlinear reaction is proportion to the enhancement of resolution. This prompt the idea of using optical bistability, which has near vertical transition, to further enhance optical resolution. However, optical bistability have mostly been demonstrated on fixed resonator or meta-surfaces with size larger than micrometer scale.
Here we show a new method to create optical bistability with Mie resonance nanoparticle. By utilizing strong photothermal heating and thermo-optical effect, we experimentally excite bistability on silicon nanoparticles. The quality factor of nanoparticles is lower than 10, which is the lowest record for observed optical bistability. This result shows the potential of creating optical bistability on nanostructure with arbitrary shape and size, as long as the excitation wavelength is tunable. We expect this study to pave the road for nanometer scale optical microscopy with dielectric nanoparticle, which can be extremely useful for both biological imaging and semiconductor inspection.

Keywords: Optical nonlinearity, Super-resolution microscopy , Optical bistability, Mie resonance, Thermo-optical effect