The University of Southampton
University of Southampton Institutional Repository

Spectroscopy of rare earth doped glasses

Spectroscopy of rare earth doped glasses
Spectroscopy of rare earth doped glasses
An extensive investigation of the spectroscopy of rare earth doped glasses is presented. Such investigations are particularly important since they provide an insight into the physical processes affecting rare earth doped fibre devices. It is a central aim of this work to demonstrate how such devices can be improved by systematic changes to the host glass.

Resonant fluorescence studies of thulium doped aluminosilicate and germanosilicate glass systems show that there are systematic variations in the Tm3+ site within the glass structure, indicating the non-random nature of the rare earth site. Fluorescence lifetime measurements in these silicate systems show a significant shortening of thulium energy level lifetimes when preforms are pulled into fibres, independent of the mechanism of decay. Furthermore, it is shown that multiphonon decay and therefore the vibrational properties of the host have a pivotal role in determining device performance. Raman spectra of a range of glass hosts are measured and analysed by new methods to enable accurate comparisons of vibrational properties to be made.

Examination of the thulium 2µm laser system indicates that glasses with maximum vibrational energies of ~920cm-1 would give improved device performance. Based on these calculations the world's first lead-germanate based optical fibre was fabricated and fully characterised. Predicted improvements in thulium performance over fluoride or silicate systems are realised.

Studies of the erbium-ytterbium 1.5µm amplifier system through Raman and lifetime measurements show that erbium site is determined purely by the ratio of phosphorus to aluminium in a silicate glass composition. It is shown that the type of erbium site determines the degree of vibrational coupling of the erbium to the highest energy vibrational modes of the glass. This coupling is linked to the performance of Er-Yb 1.5µm fibre amplifiers.

Non-exponential decay of rare earth fluorescence frequently occurs and it is shown that such decays can easily result from purely single ion multiphonon decay processes when the rare earth is in a glassy host. Furthermore, a single stretched exponential function is shown to fit all observed and modelled non-exponential decays. Use of this function enables comparisons of the degree of non-exponentiality and time evolution of such decays to be made.
Lincoln, John Roderick
b8fd86ea-45a0-4a0e-80da-38b94e3a4ec2
Lincoln, John Roderick
b8fd86ea-45a0-4a0e-80da-38b94e3a4ec2
Tropper, Anne
f3505426-e0d5-4e91-aed3-aecdb44b393c

Lincoln, John Roderick (1992) Spectroscopy of rare earth doped glasses. University of Southampton, Faculty of Science, Doctoral Thesis, 218pp.

Record type: Thesis (Doctoral)

Abstract

An extensive investigation of the spectroscopy of rare earth doped glasses is presented. Such investigations are particularly important since they provide an insight into the physical processes affecting rare earth doped fibre devices. It is a central aim of this work to demonstrate how such devices can be improved by systematic changes to the host glass.

Resonant fluorescence studies of thulium doped aluminosilicate and germanosilicate glass systems show that there are systematic variations in the Tm3+ site within the glass structure, indicating the non-random nature of the rare earth site. Fluorescence lifetime measurements in these silicate systems show a significant shortening of thulium energy level lifetimes when preforms are pulled into fibres, independent of the mechanism of decay. Furthermore, it is shown that multiphonon decay and therefore the vibrational properties of the host have a pivotal role in determining device performance. Raman spectra of a range of glass hosts are measured and analysed by new methods to enable accurate comparisons of vibrational properties to be made.

Examination of the thulium 2µm laser system indicates that glasses with maximum vibrational energies of ~920cm-1 would give improved device performance. Based on these calculations the world's first lead-germanate based optical fibre was fabricated and fully characterised. Predicted improvements in thulium performance over fluoride or silicate systems are realised.

Studies of the erbium-ytterbium 1.5µm amplifier system through Raman and lifetime measurements show that erbium site is determined purely by the ratio of phosphorus to aluminium in a silicate glass composition. It is shown that the type of erbium site determines the degree of vibrational coupling of the erbium to the highest energy vibrational modes of the glass. This coupling is linked to the performance of Er-Yb 1.5µm fibre amplifiers.

Non-exponential decay of rare earth fluorescence frequently occurs and it is shown that such decays can easily result from purely single ion multiphonon decay processes when the rare earth is in a glassy host. Furthermore, a single stretched exponential function is shown to fit all observed and modelled non-exponential decays. Use of this function enables comparisons of the degree of non-exponentiality and time evolution of such decays to be made.

Full text not available from this repository.

More information

Published date: November 1992
Organisations: University of Southampton, Physics & Astronomy

Identifiers

Local EPrints ID: 399194
URI: https://eprints.soton.ac.uk/id/eprint/399194
PURE UUID: 9f4c439e-18fa-4a0a-bab4-02288e376c83

Catalogue record

Date deposited: 16 Sep 2016 15:43
Last modified: 17 Jul 2017 18:25

Export record

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of https://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×