The invention discloses a Mach-Zehnder interference
optical fiber based on a surface
plasma effect and a sensor thereof, which belong to the field of
optical fiber sensors. According to the Mach-Zehnder interference
optical fiber based on the surface
plasma effect, a first layer of
metal film is arranged on the periphery of a sensing area optical
fiber, a
polymer layer is arranged on the peripheryof the first layer of
metal film, and a second layer of
metal film is arranged on the periphery of the
polymer layer; the thickness of the first layer of metal film is 20 to 200nm, the thickness of the
polymer layer is 150 to 180nm, and the thickness of the second layer of metal film is 20 to 50nm. According to the optical
fiber, a heavy metal film can generate surface
plasma waves under the action of light
waves, and two beams of plasma
waves can be generated in a double-layer heavy metal
film structure, so that Mach-Zehnder interference can be formed. Change of an external environment to bedetected can cause movement of an interference spectrum, and high-sensitivity detection is achieved according to the movement amount of the
wavelength. The structure is simple, the
refractive index sensitivity is high, and the sensor can work in any waveband.