High-efficiency channel drop filter based on photonic crystal noncommutative unidirectional waveguide

Abstract

A high-efficiency channel drop filter based on photonic crystal non-commutative one-way waveguide, including a photonic crystal drop waveguide and a photonic crystal formed by changing the radius of a certain dielectric column in the upper dielectric photonic crystal The crystal drop microcavity, the photonic crystal drop microcavity is connected with a photonic crystal drop waveguide, and the high efficiency channel drop filter also includes a filter for controlling the flow of light only along the incident direction without A photonic crystal non-commutative one-way waveguide that undergoes retroreflection. The photonic crystal non-commutative one-way waveguide is formed by an interface where the upper layer is a general dielectric photonic crystal and the lower layer is a magnetic photonic crystal. The microcavity is located between the photonic crystal noncommutative one-way waveguide and the photonic crystal downstream waveguide. The invention can improve the drop-off efficiency and reduce the production difficulty.

Description

technical field [0001] The invention relates to the wavelength division multiplexing technology of optical fiber communication, in particular to a channel drop filter. Background technique [0002] The current optical fiber communication system widely uses wavelength division multiplexing (WDM), which can effectively use the bandwidth of optical fiber to realize large-capacity, long-distance optical fiber communication, and can increase the number of services in the user distribution system. In the application of these wavelength division multiplexing technologies, in order to make full use of very precious bandwidth resources, the wavelength channel interval becomes narrower and narrower, and the number of channels becomes more and more. This requires that the multi-wavelength wavelength division multiplexer / demultiplexer should not only be smaller in size, but also easy to integrate. However, the size of the multi-wavelength wavelength division multiplexer / demultiplexer o...

AI Technical Summary

Problems solved by technology

However, in order to improve the drop efficiency of this structure, it is generally necessary for two point-defect microcavities to interact directly or indirectly to achieve high-efficiency wavelength drop. Extremely sensitive, making these two-photonic crystal point-defect microcavity channel down-channel filter structures extremely difficult to fabricate under the current lithography process conditions

In order to overcome this shortcoming, it is imperative to use a single photonic crystal point-defect microcavity, but the theoretical drop efficiency of a single microcavity structure is only less than 50%, which undoubtedly appears to be too low in device use.

Images