title: NIR emission studies and dielectric properties of Er(3+)-doped multicomponent tellurite glasses.
abstract: Multicomponent tellurite glasses containing altered concentrations of Er2O3 (ranging from 0 to 1 mol%) were prepared by the standard melt quenching technique. Investigations through energy dispersive X-ray spectroscopy (EDS), Raman scattering spectroscopy, Fourier transform infrared (FTIR) spectroscopy, near-infrared (NIR) emission studies and dielectric measurement techniques were done to probe their compositional, structural, spectroscopic and dielectric characteristics. The broad emission together with the high values of the effective linewidth (~63 nm), stimulated emission cross-section (9.67 × 10(-21) cm(2)) and lifetime (2.56 ms) of (4)I13/2 level for 0.5 mol% of Er(3+) makes these glasses attractive for broadband amplifiers. From the measured capacitance and dissipation factor, the relative permittivity, dielectric loss and the conductivity were computed; which furnish the dielectric nature of the multicomponent tellurite glasses that depend on the applied frequency. Assuming the ideal Debye behavior as substantiated by Cole-Cole plot, an examination of the real and imaginary parts of impedance was performed. The power-law and Cole-Cole parameters were resolved for all the glass samples. From the assessment of the emission analysis and dielectric properties of the glass samples, it was obvious that the Er(3+) ion concentration had played a vital role in tuning the optical and dielectric properties and the 0.5 mol% of Er(3+) -doped glass was confirmed as the optimum composition.
authors.affiliation: School of Pure & Applied Physics, Mahatma Gandhi University, Kottayam 686 560, India.
authors.forename: M S
authors.initials: MS
authors.lastname: Sajna
authors.affiliation: School of Pure & Applied Physics, Mahatma Gandhi University, Kottayam 686 560, India.
authors.forename: Sunil
authors.initials: S
authors.lastname: Thomas
authors.affiliation: Institute for Materials Research, University of Leeds, UK.
authors.forename: C
authors.initials: C
authors.lastname: Jayakrishnan
authors.affiliation: School of Pure & Applied Physics, Mahatma Gandhi University, Kottayam 686 560, India.
authors.forename: Cyriac
authors.initials: C
authors.lastname: Joseph
authors.affiliation: School of Pure & Applied Physics, Mahatma Gandhi University, Kottayam 686 560, India.
authors.forename: P R
authors.initials: PR
authors.lastname: Biju
authors.affiliation: School of Pure & Applied Physics, Mahatma Gandhi University, Kottayam 686 560, India. Electronic address: nvu100@yahoo.com.
authors.forename: N V
authors.initials: NV
authors.lastname: Unnikrishnan
keywords: Dielectric properties; Erbium; NIR emission; Tellurite glass