Large-bandwidth temperature-insensitive sensor based on Mach-Zehnder interferometer

Abstract

The invention discloses a large-bandwidth temperature insensitive sensor based on a Mach-Zehnder interferometer. Light source signals are input through the input optical waveguide, the power is equally divided into two asymmetric Mach-Zehnder interference arms through a 3dB power divider, the two arms are composed of first wide-strip-shaped waveguides, narrow-strip-shaped waveguides and slot waveguides which are different in length and second wide-strip-shaped waveguides which are the same in length, and different waveguide structures are connected through conical waveguides. A light field passes through the waveguide structures from the two arms, then the phase is modulated, and then the light field is interfered to the output optical waveguide through the beam combiner. The waveguides of three structures are adopted to modulate the light field phases of the two arms of the Mach-Zehnder interferometer, the high sensitivity characteristic of the slot waveguide and the integration advantage of the planar optical waveguide are combined, and the light sensor which is insensitive to temperature in a large bandwidth range, high in refractive index sensitivity, adjustable in free spectral range, high in integration level and low in cost is achieved.

Description

technical field [0001] The invention belongs to the field of optoelectronic devices, in particular to a temperature-insensitive sensor with a large bandwidth based on a Mach-Zehnder interferometer. Background technique [0002] Optical sensors have the characteristics of small size, short response time, high sensitivity, anti-electromagnetic interference, etc., and are an important branch of sensors. Among them, integrated optical waveguide sensors have the advantages of mass production, multi-channel multiplexing, and high integration, and have attracted extensive attention and research in the fields of biomolecular detection, timely diagnosis, and environmental protection. When the measured physical quantity changes, its corresponding absorption, scattering, fluorescence and other characteristics change, thus causing the change of the effective refractive index of the optical mode in the waveguide. Photonic crystals, etc.) or interferometric (Fabry-Perot interferometer, S...

AI Technical Summary

Problems solved by technology

For the strip waveguide, the optical mode is basically distributed inside the waveguide, and the contact area with the measured substance is small, usually the sensitivity is low

In addition, these sensors do not take their own temperature characteristics into account, and external thermal noise will also cause the interference wavelength to drift, reducing the resolution of the sensor itself

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