Subwavelength polarization splitter-rotator with ultra-compact footprint

Area of Science:

• Photonics
• Nanotechnology
• Integrated Optics

Background:

• Polarization control is crucial for optical communication systems.
• Existing devices often face limitations in size and performance.
• Silicon-on-insulator (SOI) offers a robust platform for integrated photonic devices.

Purpose of the Study:

• To demonstrate an ultra-compact polarization splitter-rotator (PSR).
• To utilize a discretized subwavelength nanostructure for enhanced performance.
• To achieve high performance over a broad wavelength range on the SOI platform.

Main Methods:

• Fabrication of a PSR using a discretized subwavelength nanostructure on SOI.
• Characterization of the device's performance, including insertion loss, crosstalk, and extinction ratio.
• Testing across a broad wavelength range (1500-1600 nm).

Main Results:

• Achieved ultra-compact device length of 7.92 μm.
• For TE0-TE0 mode: insertion loss <0.2 dB, crosstalk <-20 dB, extinction ratio >40 dB (1500-1600 nm).
• For TM0-TE0 mode: insertion loss <1 dB (1530-1570 nm), crosstalk <-25 dB, extinction ratio >20 dB (1500-1600 nm).

Conclusions:

• The demonstrated nanostructured PSR offers a significant advancement in miniaturization and performance.
• The device is suitable for broadband applications in integrated photonic circuits.
• This technology holds promise for next-generation optical communication and sensing systems.