arXiv subjects

Minghui Hong

Publications and source records attributed to Minghui Hong.

4 recordsLinked to original sources

arXiv2019

Dynamic high efficiency 3D meta-holography in visible range with large frames number and high frame rate based on space division multiplexing design

Hologram is an ideal method for naked eye three-dimensional (3D) display, and computer-generated holography (CGH) makes it possible to reconstruct virtual objects. However, the large pixel size of common CGH devices results in shortages in the applications of hologram, such as narrow field of view, twin images, multi-diffraction orders, et al. Meanwhile, metasurfaces consisted of subwavelength structures show great potential in controlling of light which is suitable for hologram design. There are many inspired works to achieve dynamic meta-hologram as we summary in this paper. And it can be concluded that there is still not such a research work of meta-holography with high efficiency and good display quality in the visible range that can show smooth holographic videos with a large frames number and high frame rate. In current work, we demonstrate a new design of meta-holography in visible range based on space division multiplexing metasurface which can achieve 228 different holographic frames and a very high frame rate (maximum of frame rate, 9523 FPS). Also, the metasurface consists of silicon nitride (SiNx) nanopillars with high efficiency (more than 70%). This method can not only satisfy the needs of holographic display but also be suitable for many different research fields, such as laser fabrication, photolithography, 3D forming of two-photon polymerization and optics information processing, et al.

physics.optics↗

arXiv2016

Resonant enhancement of second harmonic generation in the mid-infrared using localized surface phonon polaritons in sub-diffractional nanostructures

We report on strong enhancement of mid-infrared second harmonic generation (SHG) from SiC nanopillars due to the resonant excitation of localized surface phonon-polaritons within the Reststrahlen band. The magnitude of the SHG peak at the monopole mode experiences a strong dependence on the resonant frequency beyond that described by the field localization degree and the dispersion of linear and nonlinear-optical SiC properties. Comparing the results for the identical nanostructures made of 4H and 6H SiC polytypes, we demonstrate the interplay of localized surface phonon polaritons with zone-folded weak phonon modes of the anisotropic crystal. Tuning the monopole mode in and out of the region where the zone-folded phonon is excited in 6H-SiC, we observe a prominent increase of the already monopole-enhanced SHG output when the two modes are coupled. Envisioning this interplay as one of the showcase features of mid-infrared nonlinear nanophononics, we discuss its prospects for the effective engineering of nonlinear-optical materials with desired properties in the infrared spectral range.

physics.optics↗

arXiv2014

Sub-diffractional, volume-confined polaritons in a natural hyperbolic material: hexagonal boron nitride

Strongly anisotropic media where the principal components of the dielectric tensor have opposite signs are called hyperbolic. Such materials length exhibit unique nanophotonic properties enabled by the highly directional propagation of slow-light modes localized at deeply sub-diffractional scales. While artificial hyperbolic metamaterials have been demonstrated, they suffer from high plasmonic losses and require complex nanofabrication, which in turn induces the size-dependent limitations on optical confinement. The low-loss, mid-infrared, natural hyperbolic material, hexagonal boron nitride is an attractive alternative. We observe four series of multiple (up to seven) 'hyperbolic polariton' modes in boron nitride nanocones in two spectral bands. The resonant modes obey the predicted aspect ratio dependence and exhibit record-high quality factors (Q up to 283) in the strong confinement regime (lambda/86 in the smallest structures). These observations assert hexagonal boron nitride as a promising platform for studying novel regimes of light-matter interactions and nanophotonic device engineering.

cond-mat.mtrl-sci↗

arXiv2010

The optical microscopy with virtual image breaks a record: 50-nm resolution imaging is demonstrated

We demonstrate a new 'microsphere nanoscope' that uses ordinary SiO2 microspheres as superlenses to create a virtual image of the object in near field. The magnified virtual image greatly overcomes the diffraction limit. We are able to resolve clearly 50-nm objects under a standard white light source in both transmission and reflection modes. The resolution achieved for white light opens a new opportunity to image viruses, DNA and molecules in real time.

physics.optics↗