Highly sensitive current sensor based on fiber loop Ring-Down spectroscopy and Bent-Annealed taper No-Core fiber surrounded by magnetic fluid

The Structure and Applications of Fused Tapered Fiber Optic Sensing: A Review

“…For instance, Li et al [83] utilized a bent tapered optical fiber to enhance the decay effect of the signal, achieving high-precision RI measurement through the cascading of an S-shaped optical fiber taper and a Faraday rotation mirror. Yang et al [31] utilized a bent-annealed taper no-core fiber (NCF) immersed in magnetic fluid (MF) as the sensing head to construct a novel FLRD-based current sensing system, as shown in Figure 13. This configuration significantly enhances the evanescent field effect, resulting in a measurement sensitivity of 0.1161 µs/mA for the current sensor.…”

“…The Mach-Zehnder Interferometer (MZI) achieves high sensitivity sensing by measuring relative phase changes, suitable for measuring optical path differences [29,30]. The Fiber Loop Ringdown (FLRD) forms a light ring by connecting two optical couplers, achieving stable signal attenuation for rapid response and high sensitivity measurements [31,32]. The unique capabilities of these optical fiber structures play a crucial role in different application scenarios, providing vast possibilities for the continuous development of optical fiber sensing technology.…”