title: Temperature-insensitive bend sensor using entirely centered Erbium doping in the fiber core.
abstract: A fiber based bend sensor using a uniquely designed Bend-Sensitive Erbium Doped Fiber (BSEDF) is proposed and demonstrated. The BSEDF has two core regions, namely an undoped outer region with a diameter of about 9.38 μm encompassing a doped, inner core region with a diameter of 4.00 μm. The doped core region has about 400 ppm of an Er2O3 dopant. Pumping the BSEDF with a conventional 980 nm laser diode gives an Amplified Spontaneous Emission (ASE) spectrum spanning from 1,510 nm to over 1,560 nm at the output power level of about -58 dBm. The ASE spectrum has a peak power of -52 dBm at a central wavelength of 1,533 nm when not spooled. Spooling the BSEDF with diameters of 10 cm to 2 cm yields decreasing peak powers from -57.0 dBm to -61.8 dBm, while the central wavelength remains unchanged. The output is highly stable over time, with a low temperature sensitivity of around ~0.005 dBm/°C, thus allowing for the development of a highly stable sensor system based in the change of the peak power alone.
authors.affiliation: Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia. harith@um.edu.my
authors.forename: Harith
authors.initials: H
authors.lastname: Ahmad
authors.forename: Mohd Zamani
authors.initials: MZ
authors.lastname: Zulkifli
authors.forename: Farah Diana
authors.initials: FD
authors.lastname: Muhammad
authors.forename: Julian Md
authors.initials: JM
authors.lastname: Samangun
authors.forename: Hairul Azhar
authors.initials: HA
authors.lastname: Abdul-Rashid
authors.forename: Sulaiman Wadi
authors.initials: SW
authors.lastname: Harun