J. Wells

Lanthanide-doped Y $_{2}$ SiO $_{5}$ microcrystals were prepared using the solution combustion, solid state and sol-gel synthesis techniques. Of these, the sol-gel method yields the m…

cond-mat.mtrl-sci2022★ 14 cited

Prediction of the Optical Polarization and High Field Hyperfine Structure Via a Parametrized Crystal-Field Model for the Low Symmetry Centers in Er $^{3 +}$ Doped Y $_{2}$ SiO $_{5}$

N. L. Jobbitt, J. -P. R. Wells, M. F. Reid +3

We report on the development and application of a parametrized crystal-field model for both C $_{1}$ symmetry centers in trivalent erbium-doped Y $_{2}$ SiO $_{5}$ . High resolution Zee…

cond-mat.mtrl-sci2022★ 2 cited

Zeeman-Hyperfine Measurements of a Pseudo-Degenerate Quadruplet in CaF $_{2}$ :Ho $^{3 +}$

Kieran M. Smith, Michael F. Reid, Jon-Paul R. Wells

We report Zeeman infra-red spectroscopy of electronic-nuclear levels of $^{5}$ I $_{8} \to^{5}$ I $_{7}$ transitions of Ho $^{3 +}$ in the C $_{4v}$ (F $^{-}$ ) centre in CaF $_{2}$ with the…

cond-mat.mtrl-sci2021★ 5 cited

A Raman heterodyne determination of the magnetic anisotropy for the ground and optically excited states of Y $_{2}$ SiO $_{5}$ doped with Sm $^{3 +}$

N. L. Jobbitt, J. -P. R. Wells, M. F. Reid +1

We present the full magnetic g tensors of the $^{6}$ H $_{5/2}$ Z $_{1}$ and $^{4}$ G $_{5/2}$ A $_{1}$ electronic states for both crystallographic sites in Sm $^{3 +}$ :Y $_{2}$ SiO $_{5}$ , ded…

cond-mat.mtrl-sci2021★ 16 cited

Electron-Nuclear Interactions as a Test of Crystal-Field Parameters for Low Symmetry Systems: Zeeman-Hyperfine Spectroscopy of Ho $^{3 +}$ Doped Y $_{2}$ SiO $_{5}$

Sagar Mothkuri, Michael F. Reid, Jon-Paul R. Wells +3

High-resolution Zeeman spectroscopy of electronic-nuclear hyperfine levels of $^{5} I_{8} \to^{5} I_{7}$ transitions in Ho $^{3 +}$ :Y $_{2}$ SiO $_{5}$ is reported. Cryst…

cond-mat.mtrl-sci2019★ 43 cited

Absorption Spectra, Defect Site Distribution and Upconversion Excitation Spectra of CaF $_{2}$ /SrF $_{2}$ /BaF $_{2}$ :Yb $^{3 +}$ :Er $^{3 +}$ Nanoparticles

Sangeetha Balabhadra, Michael F. Reid, Vladimir Golovko +1

We report studies of the Yb $^{3 +}$ site distribution in Er $^{3 +}$ co-doped upconverting alkaline earth fluoride nanoparticles using high-resolution absorption measurements. Similar…

cond-mat.mes-hall2014★ 1 cited

Ultrafast reflectivity modulation in AlGaAs/InAlGaAs multiple quantum well photonic crystal waveguides

A. Z. Garcia-Deniz, P. Murzyn, A. M. Fox +6

We report an ultrafast optical tuning of the reflectivity of AlGaAs/InAlGaAs multiple quantum well photonic crystal waveguides using a reflection geometry, pump-probe technique.

cond-mat.mtrl-sci2014★ 4 cited

The dynamics of amplified spontaneous emission in CdSe/ZnSe quantum dots

D. O. Kundys, P. Murzyn, J. P. R. Wells +8

We have used the variable stripe technique and pump-probe spectroscopy to investigate both gain and the dynamics of amplified spontaneous emission from CdSe quantum dot structures.…

physics.optics2014★ 10 cited

Resolution of Discrete Excited States in InGaN Multiple Quantum Wells using Degenerate Four Wave Mixing

D. O. Kundys, J. -P. R. Wells, A. D. Andreev +6

We report on two pulse, degenerate four wave mixing (DFWM) measurements on shallow InGaN/GaN multi-quantum wells (MQWs) grown on sapphire substrates. These reveal pulse length limi…

cond-mat.mtrl-sci2013★ 8 cited

Effective-Hamiltonian parameters for \emph{ab initio} energy-level calculations of SrCl $_{2}$ :Yb $^{2 +}$ and CsCaBr $_{3}$ :Yb $^{2 +}$

A. J. Salkeld, M. F. Reid, J. -P. R. Wells +3

Calculated energy levels from recent \emph{ab initio} studies of the electronic structure of SrCl $_{2}$ :Yb $^{2 +}$ and CsCaBr $_{3}$ :Yb $^{2 +}$ are fitted with a semi-empirical "cryst…

cond-mat.mtrl-sci2011★ 11 cited

The observation of electron trap liberation in MgF $_{2}$ doped with Yb $^{2 +}$ using a two-color excitation experiment

P. S. Senanayake, J. P. R. Wells, M. F. Reid +3

We utilize the optical transitions of Yb $^{2 +}$ excited by an ultraviolet optical parametric amplifier to probe electron trap liberation in MgF $_{2}$ via the observation of a photo…

cond-mat.mtrl-sci2011★ 13 cited

Impurity-trapped excitons and electron traps in CaF $_{2}$ :Yb $^{2 +}$ and SrF $_{2}$ :Yb $^{2 +}$ probed by transient photoluminescence enhancement

P. S. Senanayake, J. P. R. Wells, M. F. Reid +3

CaF $_{2}$ :Yb $^{2 +}$ and SrF $_{2}$ :Yb $^{2 +}$ crystals have been investigated by a two-color UV + IR transient photoluminescence enhancement technique. The enhancement gives information…

cond-mat.mtrl-sci2011★ 22 cited

Transient photoluminescence enhancement as a probe of the structure of impurity-trapped excitons in CaF $_{2}$ :Yb $^{2 +}$

Michael F. Reid, Pubudu S. Senanayake, Jon-Paul R. Wells +5

We demonstrate a direct measurement of the energy levels of impurity-trapped excitons in CaF $_{2}$ :Yb $^{2 +}$ . The radically different radiative decay rates of the lowest exciton stat…

Growth and Spectroscopy of Lanthanide Doped Y2​SiO5​ Microcrystals for Quantum Information Processing

Prediction of the Optical Polarization and High Field Hyperfine Structure Via a Parametrized Crystal-Field Model for the Low Symmetry Centers in Er3+ Doped Y2​SiO5​

Zeeman-Hyperfine Measurements of a Pseudo-Degenerate Quadruplet in CaF2​:Ho3+

A Raman heterodyne determination of the magnetic anisotropy for the ground and optically excited states of Y2​SiO5​ doped with Sm3+

Electron-Nuclear Interactions as a Test of Crystal-Field Parameters for Low Symmetry Systems: Zeeman-Hyperfine Spectroscopy of Ho3+ Doped Y2​SiO5​

Absorption Spectra, Defect Site Distribution and Upconversion Excitation Spectra of CaF2​/SrF2​/BaF2​:Yb3+:Er3+ Nanoparticles