A magnetic field sensor based on a Mach-Zehnder interferometer with standard single mode fiber (SMF-28) is proposed. Here, the MZI was developed by using tapered optical fiber technique. Moreover, the Mach-Zehnder interferometer is manufactured with two tapers, with a core diameter of 25~40 μm and a length of 5 mm, and a separation between the tapers about of 4~6.5 cm. The MZI was covered by a fluid with magnetic proprieties. Performing experiments with magnets, coils and transformers, hoping that the proposed sensor offers a good option to measure the magnetic field in electrical devices.
In this paper a temperature sensing setup based on a Photonic Crystal Fiber (PCF) Mach-Zehnder Interferometer (MZI), coated with aluminum is proposed. Here, this interferometer is fabricated through the concatenation of two sections of Single Mode Fiber (SMF) with a segment of PCF between them. The SMF-PCF joint acts as beam splitter causing the excitement of PCF’s, both cladding and fundamental core modes. In the PCF-SMF union, the cladding modes couple again to the core of the SMF, and interfere with the fundamental core mode, this interaction results in an interference pattern spectrum. Moreover, the MZI was coated with aluminum, using the evaporation technique. By adding a thin metal layer to the PCF section, the general thermal coefficient of the structure changes, enhancing the sensitivity of the device. Experimental results show that a visibility of 13 dBm can be obtained and a sensitivity of 250 pm/°C. Finally, the proposed structure is simple, cost effective and easy to fabricate.
A torsion experimental sensing setup based on a Mach-Zehnder interferometer (MZI) with photonics crystal fiber is presented. The MZI was fabricated by fusion splicing a piece of photonic crystal fiber (PCF) between two segments of a single-mode fiber (SMF). Here, a spectral MZI fringe shifting is induced by applying torsion over the SMF-PCF-SMF. As a result a torsion sensitivity of 35.79 pm/ and a high visibility of 10 dB were achieved. Finally, it is shown that the sensing arrangement is compact and robust.