{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:31:49Z","timestamp":1760243509026,"version":"build-2065373602"},"reference-count":21,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2013,7,23]],"date-time":"2013-07-23T00:00:00Z","timestamp":1374537600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>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 \u03bcm encompassing a doped, inner core region with a diameter of 4.00 \u03bcm. 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 \u221258 dBm. The ASE spectrum has a peak power of \u221252 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 \u221257.0 dBm to \u221261.8 dBm, while the central wavelength remains unchanged. The output is highly  stable over time, with a low temperature sensitivity of around ~0.005 dBm\/\u00b0C, thus allowing for the development of a highly stable sensor system based in the change of the peak power alone.<\/jats:p>","DOI":"10.3390\/s130709536","type":"journal-article","created":{"date-parts":[[2013,7,23]],"date-time":"2013-07-23T13:28:05Z","timestamp":1374586085000},"page":"9536-9546","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Temperature-Insensitive Bend Sensor Using Entirely Centered Erbium Doping in the Fiber Core"],"prefix":"10.3390","volume":"13","author":[{"given":"Harith","family":"Ahmad","sequence":"first","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]},{"given":"Mohd","family":"Zulkifli","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]},{"given":"Farah","family":"Muhammad","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]},{"given":"Julian","family":"Samangun","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]},{"given":"Hairul","family":"Abdul-Rashid","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Multimedia University, 63100 Cyberjaya, Selangor, Malaysia"}]},{"given":"Sulaiman","family":"Harun","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia"}]}],"member":"1968","published-online":{"date-parts":[[2013,7,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"17834","DOI":"10.1364\/OE.18.017834","article-title":"Highly sensitive bending sensor based on Er3+-doped DBR fiber laser","volume":"18","author":"Liu","year":"2010","journal-title":"Opt. 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