Magnetic-Based Polydimethylsiloxane Microspheres for Magnetic Field Measurement

Abstract

Magnetic-based polydimethylsiloxane microspheres (MPMs) are fabricated and its applications for measurement of magnetic field are investigated. The MPMs are prepared by first incorporating the uniformly sized Mn3O4 nanocrystals into polydimethylsiloxane (PDMS) matrix, and then using a selfassembling method to obtain a chain of microspheres on the fiber taper. The MPMs are regarded as optical resonators, demonstrating whispering gallery modes (WGM) with a high Q factor in the 1310 nm band. Experimental results show that the resonance wavelengths of the WGM spectra depend on the strength of the magnetic field since the change in the applied filed cause the mechanical deformation of the MPMs, leading to a shift in the resonant wavelength of the resonator. Using as magnetic field sensors, the performances of the MPMs in terms of sensitivities and measurement ranges have been optimized. Thus, the sensitivity of 101.9 pm/mT and the measurement range up to 8 mT are achieved with a MPM (~270 μm in diameter). Besides, the performance of the MPM after two-week storage is analyzed, showing the excellent long-term stability.

Capacitive Bionic Magnetic Sensors Based on One-Step Biointerface Preparation

“…Magnetic field detection has far-reaching significance in various fields, such as navigation, biomedical engineering, space, and geophysical research. Numerous magnetic sensors, such as magneto-resistive sensors, 1 MEMS sensors, 2 optical fiber magnetic field sensors, 3 diamond magnetic sensors, 4 and such magnetic sensors have been successfully developed to explore the magnetic field signals. At the current state, most magnetosensors rely on quantum effects, which require a very sensitive interface connecting semiconductor materials that are often created through epitaxial growth.…”