Effect of The Glass Composition on The Spontaneous Emission Probabilities of Tm 3+ in TeO 2 -ZnO Glass
- PDF / 125,683 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 12 Downloads / 194 Views
FF6.16.1
Effect of The Glass Composition on The Spontaneous Emission Probabilities of Tm3+ in TeO2-ZnO Glass Gönül Özen1,2, İdris Kabalcı2, John M Collins3, Xuesheng Chen3, Ottavio Forte1 and Baldassare Di Bartolo1. 1. Department of Physics, Boston College, Chestnut Hill, MA, USA. 2. Physics Department, Istanbul Technical University, Istanbul, Turkey. 3. Department of Physics and Astronomy, Wheaton College, Norton, MA, USA.
ABSTRACT This paper reports our findings for the effect of the glass composition on the local environment of the thulium ions in the glass structure and its spontaneous and stimulated emission probabilities in the infrared region at room temperature. Absorption measurements in the UV/VIS/NIR region were used to determine spontaneous emission probabilities for the 4f-4f transitions of the thulium ion. Six bands corresponding to the absorptions of the 1G2, 3F2, 3F3, 3F4, 3H5, 3H4 from the ground level were observed. Integrated absorption cross-section of each band except that of 3H5 level was found to vary with the glass composition. Luminescence spectra of the samples were measured upon 785nm using a diode laser. Two emission bands centered about 1500nm and 1800nm were observed. The effect of the glass composition on the Judd-Ofelt Parameters and therefore on the spontaneous emission probabilities for the metastable levels of thulium ions will be discussed in detail.
INTRODUCTION Technological development of the optical telecommunications based on the growth of technologies of fiber fabrication and the laser diode has enabled efficient pumping of rare earth ions such as praseodymium, erbium [1,2]. In these systems, there are a number of interesting relationships between the active ions and the host glass. Among these glasses with low phonon energies are of interest as hosts for infrared and infrared to visible upconversion lasers [3,4]. The multiphonon relaxations are dominant in most of the oxide glasses such as borate, phosphate and silicate glasses because they have high phonon energies 1400cm-1, 1100cm-1 and 1000cm-1, respectively. However some oxide glasses have low phonon energies such as tellurite ( 780cm-1) in which the upconversion fluoresecence of thulium was observed [5]. Further more tellurite glasses compared with silicate, borate and fluoride glasses show many desirable features including mechanical strength and chemical durability. In the present work, the spectroscopic properties of thulium in TeO2-ZnO glasses have been investigated by means of absorption and luminescence measurements.
FF6.16.2
EXPERIMENTAL In the experiments, glass samples were prepared with the compositions of (1x)TeO2 + (x)ZnO where x= 0.2, 0.3 and 0.4 in molar ratio. Batches of 5 g were thoroughly mixed and melted in a lidded platinum crucible at 800oC for 60 minutes. This was done in an electrically heated furnace maintained in air atmosphere. The glass melts were removed from the furnace and then quenched in a stainless steel mould. A series of thulium doped glasses were also prepared using the same tem
Data Loading...
