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We propose and simulate a compact (∼29.5 µm-long) nonvolatile polarization switch based on an asymmetric Sb2Se3-clad silicon photonic waveguide. The polarization state is switched between TM0and TE0mode by modifying the phase of nonvolatile Sb2Se3between amorphous and crystalline. When the Sb2Se3is amorphous, two-mode interference happens in the polarization-rotation section resulting in efficient TE0-TM0conversion. On the other hand, when the material is in the crystalline state, there is little polarization conversion because the interference between the two hybridized modes is significantly suppressed, and both TE0and TM0modes go through the device without any change. The designed polarization switch has a high polarization extinction ratio of > 20 dB and an ultra-low excess loss of < 0.22 dB in the wavelength range of 1520-1585 nm for both TE0and TM0modes.
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This content will become publicly available on December 22, 2026
Interferometric modal splitting enables broadband, dual-polarization on-chip spectroscopy
The modal dispersion of waveguides typically limits integrated photonic devices to operation with a single polarization state. In this work, we propose a generic mode separation technique we call “interferometric mode splitting” (IMS), which enables guided modes to be separated over wide bandwidths with a large extinction ratio. To demonstrate the general principle of IMS, we show that an unmodified thermally driven silicon photonic Fourier transform spectrometer exhibits a polarization-separating effect in the frequency domain, even though only one polarization-insensitive detector is used. Using this effect, we experimentally demonstrate a simple on-chip spectrometer capable of extracting two-polarization spectra over a wide 1480–1630 nm bandwidth with a greater than 20 dB polarization extinction ratio. These specifications would be highly challenging to achieve using existing, conventional on-chip polarization-splitting techniques. Though we focus on this specific realization of IMS, we also show that IMS is general to various on-chip spectrometer architectures, other spatial modes, and technologies other than thermally driven Fourier transform spectrometers. Interferometric mode splitting shows promise as a general approach for robust and fundamentally broadband detection of orthogonal modes in guided-wave sensing.
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- Award ID(s):
- 2217453
- PAR ID:
- 10679098
- Publisher / Repository:
- OPTICA
- Date Published:
- Journal Name:
- Optica
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2334-2536
- Page Range / eLocation ID:
- 1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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