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Dan Sporea   Dr.  Senior Scientist or Principal Investigator 
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Dan Sporea published an article in March 2018.
Top co-authors See all
Elfed Lewis

348 shared publications

Optical Fibre Sensors Research Centre, Department of Electronic and Computer Engineering, University of Limerick, Limerick, Ireland

Gaetano Scamarcio

156 shared publications

Istituto di Fotonica e Nanotecnologie, CNR, 70126 Sede di Bari, Italy

Manfred Rothhardt

122 shared publications

Leibniz Institute of Photonic Technology, 07745 Jena, Germany

Martin Becker

121 shared publications

Leibniz Institute of Photonic Technology (IPHT), Albert-Einstein-Strasse 9, 07745 Jena, Germany;(M.B.);(J.D.);(M.R.);(H.B.)

L. Petit

116 shared publications

Laboratory of Photonics, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, Finland;(N.O.);(U.A.)

Publication Record
Distribution of Articles published per year 
(2007 - 2018)
Total number of journals
published in
Publications See all
Article 9 Reads 3 Citations Long Period Gratings in unconventional fibers for possible use as radiation dosimeter in high-dose applications Andrei Stancălie, Dan Sporea, Daniel Neguţ, Flavio Esposito,... Published: 01 March 2018
Sensors and Actuators A: Physical, doi: 10.1016/j.sna.2018.01.034
DOI See at publisher website
Article 0 Reads 1 Citation Optimized Spectrometers Characterization Procedure for Near Ground Support of ESA FLEX Observations: Part 1 Spectral Cal... Laura Mihai, Alasdair Mac Arthur, Andreas Hueni, Iain Robins... Published: 13 February 2018
Remote Sensing, doi: 10.3390/rs10020289
DOI See at publisher website ABS Show/hide abstract
The paper presents two procedures for the wavelength calibration, in the oxygen telluric absorption spectral bands (O2-A, λc = 687 nm and O2-B, λc = 760.6 nm), of field fixed-point spectrometers used for reflectance and Sun-induced fluorescence measurements. In the first case, Ne and Ar pen-type spectral lamps were employed, while the second approach is based on a double monochromator setup. The double monochromator system was characterized for the estimation of errors associated with different operating configurations. The proposed methods were applied to three Piccolo Doppio-type systems built around two QE Pros and one USB2 + H16355 Ocean Optics spectrometers. The wavelength calibration errors for all the calibrations performed on the three spectrometers are reported and potential methodological improvements discussed. The suggested calibration methods were validated, as the wavelength corrections obtained by both techniques for the QE Pro designed for fluorescence investigations were similar. However, it is recommended that a neon emission line source, as well as an argon or mercury-argon source be used to have a reference wavelength closer to the O2-B feature. The wavelength calibration can then be optimised as close to the O2-B and O2-A features as possible. The monochromator approach could also be used, but that instrument would need to be fully characterized prior to use, and although it may offer a more accurate calibration, as it could be tuned to emit light at the same wavelengths as the absorption features, it would be more time consuming as it is a scanning approach.
PROCEEDINGS-ARTICLE 0 Reads 0 Citations Gamma Radiation Measurements using an Optical Fiber Laser Rosa Ana Perez-Herrera, Andrei Stancalie, Pablo Cabezudo, Da... Published: 01 January 2018
26th International Conference on Optical Fiber Sensors, doi: 10.1364/ofs.2018.wf37
DOI See at publisher website
PROCEEDINGS-ARTICLE 0 Reads 0 Citations Gamma radiation effects on Long Period Gratings and transmitted power in different optical fibers: towards dosimetry app... Flavio Esposito, Andrei Stăncălie, Rajeev Ranjan, Daniel Neg... Published: 01 January 2018
26th International Conference on Optical Fiber Sensors, doi: 10.1364/ofs.2018.tue85
DOI See at publisher website
BOOK-CHAPTER 8 Reads 0 Citations Optical Fiber Sensors in Ionizing Radiation Environments Dan Sporea Published: 21 November 2017
Handbook of Optical Fibers, doi: 10.1007/978-981-10-1477-2_25-1
DOI See at publisher website
Article 2 Reads 6 Citations Arc-induced Long Period Gratings in standard and speciality optical fibers under mixed neutron-gamma irradiation Andrei Stancălie, Flavio Esposito, Rajeev Ranjan, Petrişor B... Published: 20 November 2017
Scientific Reports, doi: 10.1038/s41598-017-16225-4
DOI See at publisher website PubMed View at PubMed ABS Show/hide abstract
In this paper, for the first time, the effects of mixed neutron and gamma flux on the spectral and sensing responses of Long Period Gratings (LPGs) are thoroughly analyzed. Six LPGs written by means of Electric Arc Discharge (EAD) technique in standard and speciality fibers, including radiation-hardened ones, were tested. The EAD technique was chosen because it enables the writing of gratings both in standard and not photosensitive fibers. The experiments have been carried out in a “TRIGA” pulsed nuclear reactor and the LPGs were irradiated by a gamma-ray dose-rate of 9 Gy/s and a mean 1.2∙1012 n/(cm2s) neutron flux. Real time monitoring was performed for a comparative investigation of LPGs’ response, in terms of radiation sensitivity and wavelength shift. Experiments show that LPG in a radiation-resistant fiber exhibits resonant wavelength shift higher than LPG in standard fiber. The changes of temperature sensitivity due to radiation were experimentally established by comparison of pre- and post-radiation characterization, indicating that radiation effects induce a slight increase of the temperature sensitivity, except for the LPG in pure-silica fiber. Theoretical and numerical analysis was combined with experimental data for evaluation LPGs’ parameters changes, such as refractive index and thermo-optic coefficient, after exposure to radiation.