Enhanced polarization-independent two-layer five-port grating with covering layer

2021 ◽  
pp. 2150348
Author(s):  
Bowen Gong ◽  
Huiying Wen

In this paper, an enhanced polarization-independent two-layer five-port grating with covering layer is proposed. The rigorous coupled-wave analysis (RCWA) is used to predict grating parameters. In addition, the total efficiency of the polarization-independent five-port grating with covering layer can exceed 80% with the good uniformity of 1.97% for TE and TM polarization. The inherent coupling mechanism and the electric field energy distribution of the gratings are explained well under TE and TM polarization by the simplified mode method (SMM) and the finite element method (FEM). According to the reported five-port gratings, the proposed transmission five-port grating with a covering layer has good uniformity for TE and TM polarization. Moreover, the grating can be protected and the groove of the grating can be kept clean by adding a covering layer during the actual fabrication. At the same time, the fabrication errors of the two-layer five-port diffraction grating are further considered. Therefore, the numerically simulated five-port grating with covering layer has a wide application prospect in precision displacement measurement and holographic projection imaging.

2018 ◽  
Vol 32 (31) ◽  
pp. 1850386 ◽  
Author(s):  
Chenhao Gao ◽  
Bo Wang ◽  
Hongtao Li ◽  
Kunhua Wen ◽  
Ziming Meng ◽  
...  

We propose and investigate a polarization-independent high-efficiency encapsulated subwavelength grating with a connecting layer in this paper. Numerical simulated method of rigorous coupled-wave analysis is adopted for optimization. Based on the simulated precise results, a simplified modal method is used to give perspicuous physical propagating fundamentals and explain wideband performance in the grating, where the coupled efficiencies by means of the simplified modal method are to be in conformity with the calculated values of the rigorous coupled-wave analysis for TE and TM polarizations. Compared with the researched surface-relief polarization-independent single-port grating, efficiencies are improved with 98.1% for TE polarization and 98.2% for TM polarization. Hence, the novel gratings with some superiorities are suitable for promising photonic devices.


2013 ◽  
Vol 310 ◽  
pp. 481-485
Author(s):  
Ke Zhao ◽  
Xiao Min Lei ◽  
Guo Feng Xie ◽  
Wen Hua Xiong

Based on a silicon-on-insulator (Silicon-on-insulator, SOI) material system design and optimization of a high performance, the polarization independent of 1 × 3 subwavelength grating stars beam splitter. By a rigorous coupled-wave analysis method showed that, in the 1550nm wavelength range, at vertical incidence, the device on the transverse electric field (transverse electric, TE) ,the 0 and ± 1 order transmittance is 31%, 32%, 32%,respectively; cross the magnetic field (transverse magnetic, TM), the 0 and ± 1 transmittance is 33%, 32%, 32%, respectively.


2020 ◽  
pp. 2150004
Author(s):  
CHEN FU ◽  
BO WANG ◽  
JIMIN FANG

In this paper, the sandwiched configuration is designed under normal incidence with zeroth order eliminated so as to design a highly-efficient four-port output with polarization independence. Through rigorous coupled-wave analysis method, the splitting parameters are calculated to get a good polarization-independence effect, where the four reflective efficiencies are over 20%, respectively. The final findings show that this grating has good diffraction characteristics and high stability in practice. Furthermore, the coupling mechanism of grating can be explained for the cancellation of the zeroth order by studying the overlap integral and the electric field distribution.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1567
Author(s):  
Shinpei Ogawa ◽  
Shoichiro Fukushima ◽  
Masaaki Shimatani

Hexagonal boron nitride (hBN) exhibits natural hyperbolic dispersion in the infrared (IR) wavelength spectrum. In particular, the hybridization of its hyperbolic phonon polaritons (HPPs) and surface plasmon resonances (SPRs) induced by metallic nanostructures is expected to serve as a new platform for novel light manipulation. In this study, the transmission properties of embedded hBN in metallic one-dimensional (1D) nanoslits were theoretically investigated using a rigorous coupled wave analysis method. Extraordinary optical transmission (EOT) was observed in the type-II Reststrahlen band, which was attributed to the hybridization of HPPs in hBN and SPRs in 1D nanoslits. The calculated electric field distributions indicated that the unique Fabry–Pérot-like resonance was induced by the hybridization of HPPs and SPRs in an embedded hBN cavity. The trajectory of the confined light was a zigzag owing to the hyperbolicity of hBN, and its resonance number depended primarily on the aspect ratio of the 1D nanoslit. Such an EOT is also independent of the slit width and incident angle of light. These findings can not only assist in the development of improved strategies for the extreme confinement of IR light but may also be applied to ultrathin optical filters, advanced photodetectors, and optical devices.


2011 ◽  
Vol 211-212 ◽  
pp. 465-468
Author(s):  
De Wei Chen

Since the development almost a decade ago of the first biosensor based on surface plasmon resonance (SPR), the use of this technique has increased steadily. In this study, we theoretically investigated the sensing character of SPR sensor with reflection type metallic with Rigorous Coupled Wave Analysis (RCWA) method, and the mechanism is analyzed by the field distribution. It is found that the sensitivity of negative diffraction order, which goes higher quickly as the resonant angle increases, is much greater than that of positive diffraction order.


2021 ◽  
Vol 9 ◽  
Author(s):  
Ryoya Hiramatsu ◽  
Ryo Takahashi ◽  
Ryoto Fujiki ◽  
Keisuke Hozo ◽  
Kanato Sawai ◽  
...  

In this paper, a hybrid numerical simulation tool is introduced and performed for GaInN-based light-emitting diodes (LEDs) with metal-embedded nanostructure to theoretically predict external quantum efficiency (EQE), which composed of finite-difference time-domain, rigorous coupled wave analysis, and ray tracing. The advantage is that the proposed method provides results supported by sufficient physical background within a reasonable calculation time. From the simulation results, the EQE of LED with Ag-nanoparticles embedded nanostructure is expected to be enhanced by as high as ∼1.6 times the conventional LED device in theory.


Sign in / Sign up

Export Citation Format

Share Document