Spectral Analysis of Nd 3+ Doped Lead Borosilicate Glasses for Efficient Broadband Laser Amplification

Abstract

In this investigation, Nd 3+ doped lead borosilicate glasses (LBS) were prepared with chemical composition of (30-x) PbO – 40 H3BO3 –10 SiO2 – 10 Al2O3 – 10 LiF – x Nd2O3 (where x varies from 0.0, 0.1, 0.5, 1.0 and 2.0 mol%) by conventional melt-quenching method. The spectroscopic analysis can be done using absorption, emission and decay measurements. The oscillator strengths (fexp and fcal) and the evaluated Judd-Ofelt (JO) intensity parameters (Ωλ, λ = 2, 4 and 6) determined from the absorption spectrum. From the emission spectra, three NIR bands observed at 903, 1060 and 1334 nm corresponding to the 4 F3/2→ 4 I9/2, 4 F3/2 → 4 I11/2 and 4 F3/2 → 4 I13/2 transitions, respectively for which the effective bandwidths (ΔλP), radiative transition probabilities (AR) branching ratios (βR) and stimulated emission cross-sections (σse) are also evaluated. The intensities of emission bands increased with the increase of Nd 3+ ions concentration upto 1.0 mol% and then decreased at higher concentrations due to the concentration quenching. From the analysis of emission properties, it is concluded that the Nd 3+ doped LBS glasses could be useful for various photonic applications in different fields. Introduction. In the present scenario, the multicomponent oxide glasses have been attracted the several researchers and technologists due to their unique properties such as trouble-free casting, good transparency, solubility of rare earth ions and long term stability [1]. However, due to the increasing demand of the rare earth doped multi-component oxide laser glasses in various applications such as higher order harmonic generation [2], time-resolved laser spectroscopy [3], plasma generation [4] and in many areas, a good host is highly essential to improve the quantum efficiency to meet the aforesaid applications. In the process of searching various oxide glasses, the host glasses with heavy metallic components such as lead oxide, aluminum oxide and silicon dioxide are found to have the ultrafine transparency, high thermal stability, low melting point, infrared transparency, corrosion resistance and also good solubility of rare earth ions [5]. In these multiconstituents, the role of lead in the glass network is to reduce the phonon energy of borate (~1400cm-1) and also to increase the mechanical stability by lowering the melting temperature. Hence, in the present study lead borosilicate glasses (LBS) are chosen as a host matrix to meet the specified applications. Among the available rare earth ions, the neodymium (Nd 3+) ion is identified as one of the most efficient ions for solid state lasers with the emission wavelength at 1060 nm as well as the possibility for lasing action at other wavelengths such as 1800, 1350 and 880 nm which are be useful for broadband laser amplifiers and other photonic applications.