Directional coupling type TM polarizer and beam splitter based on sub-wavelength grating

Abstract

The invention discloses a directional coupling type TM polarizer and a beam splitter based on sub-wavelength grating. A sub-wavelength grating is introduced to an asymmetric directional coupler, and a wave guide having a sub-wavelength grating is used as a channel 1, and another waveguide without the sub-wavelength grating is used as a channel 2. When an incident light beam is transmitted through the channel 1, a TE polarization state light is reflected by the sub-wavelength grating, and a TM polarization state light is coupled with a channel 2 for output by a sub-wavelength grating area, and a TM polarizer is realized. When the incident light beam is transmitted through the channel 2, the TE polarization state light is transmitted for the output by the channel 2, and the TM polarization state light is coupled with the channel 1 for the output by the sub-wavelength grating area, and a TE and TM polarization beam splitter is realized. By using one single device, the polarizer function and the beam splitter function are realized, and therefore an integration level of an optoelectronic device is greatly improved, a structure is simple, and is easy to design and produce.

Description

technical field [0001] The invention belongs to the technical field of micro-nano optoelectronics and silicon photonic devices, and specifically refers to a directional coupling type TM polarizer and a beam splitter based on a subwavelength grating. Background technique [0002] Silicon on insulator (silicon on insulating substrate), as a new silicon-based integrated circuit and optoelectronic material, has been widely used due to its large refractive index difference and compatibility with CMOS. However, its polarization-sensitive characteristics have limited its application, so how to develop polarization-controlled devices is the focus of current research on micro-nano optoelectronic devices. Polarizing beam splitters and polarizers are important devices to solve how to transmit light of two polarization states simultaneously, and they are also the most widely used devices in integrated optical circuits. The miniaturization of integrated circuits requires reducing the si...

AI Technical Summary

Problems solved by technology

The miniaturization of integrated circuits requires reducing the size of the device, but this will be limited by the process, so the method of reducing the size of the device to increase the integration has encountered a bottleneck in the manufacturing process

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