Stably tuned add-drop filter based on bottle-shaped whispering gallery mode microcavity

Abstract

The invention discloses a stable tuning Add-drop filter based on a bottleneck-shaped echo wall mode microcavity. The stable tuning Add-drop filter comprises the bottleneck-shaped echo wall mode microcavity (1), an input waveguide (2), an output waveguide (3), a first displacement apparatus (4) and a second displacement apparatus (5), wherein the outline of the bottleneck-shaped echo wall mode microcavity (1) changes axially with a parabola-like shape; the other end of the microcavity is used for leading out a non-resonant optical signal; the output waveguide (3) is used for leading out a resonant optical signal in the microcavity; and the first displacement apparatus (4) and the second displacement apparatus (5) enable the input waveguide and the output waveguide to move axially along the bottleneck-shaped microcavity respectively so as to change positions of coupling points to further change coupling coefficients k1 and k2. According to the stable tuning Add-drop filter, the stable fine tuning on bandwidth and output spectrum frequency is realized; and the shortcoming that the conventional echo wall mode based Add-drop filter is affected by the environment easily in tuning is overcome.

Description

technical field [0001] The invention belongs to the technical field of optical devices, and in particular relates to an Add-drop filter which can be stably and finely tuned based on a bottle-shaped whispering gallery mode microcavity. Background technique [0002] Optical add-drop filters have become important components in many applications, including optical communication, optical sensing, and optical signal processing systems. Add-drop filters are usually used to select or insert certain specific wavelengths from optical broadband signals. The Add-drop filter has three important indicators: spectral selectivity (Q value), output spectral efficiency, and spectral tunability. [0003] In the past two decades, different types of optical Add-drop filters have been widely studied, including all-fiber Add-drop filters and Add-drop filters based on whispering gallery mode microcavities, all of which have their own Features and benefits. An all-fiber add-drop filter such as CN...

AI Technical Summary

Problems solved by technology

The way to realize it is to use the mode field distribution characteristics of a bottle-mouth-shaped microcavity with nanometer-scale protrusions on the surface, and use a displacement device to adjust the coupling point position (micron scale) of the input and output waveguides and the microcavity, thereby changing the coupling coefficient. kappa 1 , κ 2 At the same time, the contact between the input and output waveguides and the surface of the microcavity is maintained, thereby realizing stable and fine tuning of the bandwidth and output spectral efficiency, and overcoming the shortcomings of the traditional Add-drop filter based on the whispering gallery mode, which is easily affected by the environment.

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