Abstract

Polarizers are the essential components to purify the polarization in the system demanding for the single polarization propagation. Polarizers with broad working bandwidth, low excess loss (EL) and large polarization extinction ratio (PER) are usually preferred. TE polarizers with ultrahigh performance have been demonstrated. However, the bandwidth of the previously reported transverse magnetic (TM) integrated polarizers is still limited to be < ∼160 nm when the EL < 1 dB and PER > 20 dB are simultaneously satisfied. In this paper, an all-silicon integrated TM polarizer with > 415 nm working bandwidth from 1260 nm to 1675 nm is experimentally demonstrated. The device consists of a double slot structure with 180° Euler bending on silicon waveguides. The effective refractive index (ERI) for TE polarization in the double slot structure is lower than that of the silica buffer/cladding while ERI for TM polarization is much larger than that of the silica buffer/cladding. Thus, TE polarization will leak into the substrate while TM polarization can propagate through the device with low loss. The measured transmission spectra for the fabricated polarizer show low EL < 0.9 dB and large PER > 25 dB over an ultrabroad band beyond the O-, E-, S-, C-, L-and U- bands.

All-silicon TM polarizer covering the 1260–1675 nm bandwidth using a band engineered subwavelength grating waveguide

Lei Zhang, Zhenzhao Guo, Xiaofei Gu, Jinbiao Xiao, Ting Feng, and Shengbao Wu
Opt. Lett. 48(13) 3431-3434 (2023)

High-performance all-silicon polarizer with 415 nm bandwidth

Weixi Liu, Daoxin Dai, and Yaocheng Shi
Opt. Lett. 46(6) 1321-1324 (2021)

Ultrahigh extinction ratio and ultra-low insertion loss silicon TE polarizer covering 1260–1675 nm bandwidth

Xiao Li, Zongxing Lin, and Sailing He
Opt. Lett. 47(8) 2065-2068 (2022)

Subwavelength-grating-assisted silicon polarization rotator covering all optical communication bands

Hongnan Xu and Yaocheng Shi
Opt. Express 27(4) 5588-5597 (2019)

Anisotropic metamaterial-assisted all-silicon polarizer with 415-nm bandwidth

Hongnan Xu, Daoxin Dai, and Yaocheng Shi
Photon. Res. 7(12) 1432-1439 (2019)