Magnetic field sensor based on PDMS incorporated with ferromagnetic nanocrystals

In this paper, a three-beam Fabry-Perot interferometric senor for magnetic field and temperature measurement is proposed, which is based on a polymer capped on the cleaved end of a single mode fiber and another SMF is aligned with it. The employed polymer is polydimethylsiloxane (PDMS) incorporated with ferromagnetic nanocrystals (Mn₃O₄). The proposed structure is compact and easy to fabricate, which can improve the sensitivity. The measured sensitivity of magnetic field is -560 pm/mT around 1550 nm. The proposed sensor possesses the following potential applications, such as petroleum survey, electric power industry, biomedicine, aerospace engineering and other fields.