Optical properties and energy transfer processes in (Tm3+, Nd3+) doped tungstate fluorophosphate glass

Abstract

We investigate the linear optical properties and energy transfer processes in tungstate fluorophosphate glass doped with thulium ͑Tm 3+ ͒ and neodymium ͑Nd 3+ ͒ ions. The linear absorption spectra from 370 to 3000 nm were obtained. Transitions probabilities, radiative lifetimes, and transition branching ratios were determined using the Judd-Ofelt ͓Phys. Rev. 127, 750 ͑1962͒; J. Chem. Phys. 37, 511 ͑1962͔͒ theory. Frequency up-conversion to the blue region and fluorescence in the infrared were observed upon pulsed excitation in the range of 630-700 nm. The excitation spectra of the luminescence were obtained to understand the origin of the signals. The temporal decay of the fluorescence was measured for different concentrations of the doping ions. Energy transfer rates among the Tm 3+ and Nd 3+ ions were also determined.

Near Infrared Broadband Emission and Spectroscopic Properties of Tm3+/Nd3+ Codoped Optical Fiber

“…The JO parameters obtained in the present work indicated the trend as Ω 2 > Ω 4 > Ω 6 as the same trend has been found in previous reports (Chung and Heo, 2001); (Martinez et al, 1998); (Thomas et al, 1992); (Walsh and Barnes, 2004). Nevertheless, the trend of the Tm 3+ /Nd 3+ codoped glass (Brandão et al, 2006) showed higher Ω 6 than Ω 4 (Ω 2 > Ω 6 > Ω 4 ). Since the intensity parameter ( 2 ) is related to the degree of covalence (Digonnet, 1993), the large value of  2 in the present work indicates the presence of covalent bonding between Tm 3+ and Nd 3+ .…”

“…The values of the JO parameters were, respectively, 8.1610 -24 , 3.2010 -24 and 2.6710 -24 m 2 for  2 ,  4 and  6 . The JO intensity parameters of the present work compared with the results of the Tm 3+ /Nd 3+ codoped glasses (Brandão et al, 2006); (Chung and Heo, 2001), the Tm doped fibers (Peterka et al, 2004); (Walsh and Barnes, 2004), and the Nd doped fiber preform and glass (Martinez et al, 1998); (Thomas et al, 1992) are listed in Table 2.…”

“…In order to broaden the emission bandwidth, the most attractive method is that RE ions are codoped into the core of the fiber where the energy transfer (ET) process takes place between different species of ions (Tanabe, 2002). Moreover, such ET process favours emission efficiency and enhances the gain of an amplifier (Brandão et al, 2006).…”

“…Although the enhancement of upconversion emission efficiency by using Nd 3+ as a sensitizer for Tm 3+ (Rakov et al, 2009); (Rakov et al, 2002) and the ET process between them (Brandão et al, 2006); (Chung and Heo,200); (Lahoz et al, 2008); (Tanabe et al, 2000) were reported in different host materials, no broadband near infrared (NIR) emission of Tm 3+ /Nd 3+ codoped silicate optical fiber was investigated. In this study, a wide range of NIR emission spectrum broadening from 1215 to 1515 nm with FWHM of 158 nm has been studied in Tm 3+ /Nd 3+ codoped fiber upon exciting at 633 nm.…”

Desenvolvimento de técnica para nucleação de nanopartículas metálicas em vidros de germanato dopados com íons de túlio para aplicações em dispositivos fotônicos.

“…Os materiais dopados com Tm 3+ têm atraído grande interesse dos pesquisadores devido as suas aplicações em dispositivos como laser de estado sólido, LEDs, displays e dispositivos de armazenamento de dados [4,[8][9][10][11][12], devido à sua intensa emissão de luz azul, em torno de 480 nm, quando utilizado em sistemas que envolvem codopagem com Yb 3+ , além da área médica que utiliza a região do infravermelho [13]. Os vidros de germanato dopados com vários íons de terras-raras • Aumento no índice de refração linear e não-linear do vidro;…”