In this paper, we report a two-layer five-port diffraction grating by a polarization-independent design under normal incidence. To be different from conventional five-port gratings, initially, we design a novel two-layer grating with operation in transmission. Next, we firstly design a polarization-independent grating with five-port splitting output. On the one hand, the accurate grating vector parameters are optimized using rigorous coupled-wave analysis (RCWA) approach. On the other hand, the inherent coupling mechanism happened in the grating region can be well explained by employing simplified modal method (SMM). More importantly, all reported conventional five-port beam splitter gratings were designed based on polarization dependent. Although they could obtain high diffraction efficiency for TE or TM polarization, it requires more complicated and time-consuming fabrication processes in practical grating applications. Thus, this work can open up a possible thought for designing polarization-independent multi-port beam splitter diffraction gratings.

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Polarization-Independent Two-Layer Grating With Five-Port Splitting Output Under Normal Incidence

The ultrashort, ultrahigh intensity pulse laser has been fully developed in past three decades Chirped pulse amplification (CPA) system plays an important role in the generation of the ultrashort, ultrahigh intensity pulse laser Pulse compression gratings (PCGs) are the key element of CPA system and determine the performance and lifetime of the whole system We introduce the principle of CPA system and the performance requirements of PCGs Then the development status of PCGs, including Au-coated grating, multilayer dielectric grating (MDG), and metal MDG, is fully reviewed Finally, the development prospect of PCGs in the future is presented Our study is helpful for comprehensive understanding of PCGs

https://www.spiedigitallibrary.org/journals/optical-engineering/volume-60/issue-2/020902/Review-of-pulse-compression-gratings-for-chirped-pulse-amplification-system/10.1117/1.OE.60.2.020902.pdf

Review of pulse compression gratings for chirped pulse amplification system

Broadband achromatic phase retarder based on metal-multilayer dielectric grating

TiO2/airgap-based polarizing beam splitter: design, simulation, and fabrication based on MEMS technologies

A new reflecting polarizing beam splitter (RPBS), based on a metal–multilayer dielectric grating (MMDG), was designed using rigorous coupled wave analysis method and a genetic algorithm. The RPBS reflects the TE wave in the −1st order and TM wave in the 0th order for 800 nm. The optimized RPBS has an extinction ratio of over 20 dB, from 765 nm to 823 nm, and a large angle, from 43.8° to 60°. At 800 nm, the extinction ratios of the 0th and −1st orders reach a maximum of 41.0 dB and 53.2 dB, respectively. Furthermore, analysis suggests that the designed RPBS allows sufficient manufacture tolerance. These results show the potential of MMDGs in fabrication of a RPBS, which can be widely used in optical systems.

Optimization design and analysis of reflecting polarizing beam splitter based on metal–multilayer dielectric grating for 800 nm

This article deals with designing broadband and high efficiency metal multi-layer dielectric grating (MMDG) used to
compress and stretch ultra-short laser pulse. The diffraction characteristics of MMDG are analyzed with the method of
rigorous coupled-wave analysis (RCWA). Taking the diffraction efficiency of the -1 order as the value of merit function,
the parameters such as groove depth, residual thickness, duty cycle are optimized to obtain broadband and high
diffraction efficiency. The optimized MMDG shows an ultra-broadband working spectrum with the average efficiency
exceeding 97% over 135nm wavelength centered at 800nm and TE polarization. The optimized MMDG should be useful
for chirped pulse amplification.

Zhao Wang

Papers

Optimization design and analysis of reflecting polarizing beam splitter based on metal–multilayer dielectric grating for 800 nm

Broadband and high-efficiency metal-multilayer dielectric grating centered at 800 nm based on non-quarter wave coatings as reflective mirror

Terahertz beam splitter based on mode coupling of subwavelength waveguides