PMC

Schematic diagram of the experimental setup for investigating the sensing properties.

Dispersion profiles of the NCF and magnetic fluids (MFs) with different refractive indices (RIs).

Transmission spectra of the sensing structures with the RI of the MF of (a) 1.45691 and (b) 1.45926. The length of the NCF is 3.5 cm.

(a) Transmission spectra of the as-fabricated sensing structures, (b) the corresponding spectra at the short wavelength regime and (c) at the long wavelength regime.

Relationship between the CWD and the magnetic field intensity for the sensing structures covered with an MF of different RIs. The length of the NCF is 3.5 cm.

(a) Schematic of the proposed sensor; (b) picture of the as-fabricated sensor; (c) simulation of energy distribution within the no-core fiber (NCF) for the guided (); (d) index-matched () and (e) leaky () cases, respectively.

Transmission spectra of the sensing structures consisting of the NCF with lengths of (a) 2.5 cm and (b) 3.5 cm; (c) the relationship between the coupling wavelength dip (CWD) and the magnetic field intensity.