Search Results - "Sweeney, S.J."

Bi incorporation in GaAs(100)-2×1 and 4×3 reconstructions investigated by RHEED and STM by Bastiman, F., Cullis, A.G., David, J.P.R., Sweeney, S.J.

“…Bi acts as a surfactant in molecular beam epitaxy (MBE) growth on GaAs(100). Incorporation is achieved by disequilibrium at growth temperatures below ∼450°C…”
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Non-stoichiometric GaAsBi/GaAs (100) molecular beam epitaxy growth by Bastiman, F., Mohmad, A.R.B., Ng, J.S., David, J.P.R, Sweeney, S.J.

“…The growth of III–V bismuthides is complicated by the low incorporation efficiency of Bi in GaAs, leading either to the formation of metallic Bi droplets or…”
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Improved Optoelectronic Properties of Rapid Thermally Annealed Dilute Nitride GaInNAs Photodetectors by Tan, S.L., Hunter, C.J., Zhang, S., Tan, L.J.J., Goh, Y.L., Ng, J.S., Marko, I.P., Sweeney, S.J., Adams, A.R., Allam, J., David, J.P.R.

“…We investigate the optical and electrical characteristics of GaInNAs/GaAs long-wavelength photodiodes grown under varying conditions by molecular beam epitaxy…”
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Direct measurement of facet temperature up to melting point and COD in high-power 980-nm semiconductor diode lasers by Sweeney, S.J., Lyons, L.J., Adams, A.R., Lock, D.A.

“…The authors describe a straightforward experimental technique for measuring the facet temperature of a semiconductor laser under high-power operation by…”
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MOVPE growth and characterization of Ga(NAsP) laser structures monolithically integrated on Si (001) substrates by Liebich, S., Sweeney, S.J., Zimprich, M., Ludewig, P., Beyer, A., Volz, K., Stolz, W., Kunert, B., Hossain, N., Jin, S.R.

“…In this work we focus on the MOVPE growth of Ga(NAsP) laser structures for electrical current injection lattice matched on exactly orientated Si substrates and…”
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Femtosecond laser ablation (fs-LA) XPS – A novel XPS depth profiling technique for thin films, coatings and multi-layered structures by Baker, M.A., Bacon, S.R., Sweeney, S.J., Hinder, S.J., Bushell, A., Nunney, T.S., White, R.G.

“…[Display omitted] •Femtosecond laser ablation is an exciting new approach to XPS depth profiling.•Results show no chemical damage induced by femtosecond laser…”
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Thermoluminescence glow curve study of beta irradiated germanium doped core fibre with different dopant concentrations by Termsuk, C., Sweeney, S.J., Shenton-Taylor, C.

“…This paper reports the assessment of commercial Ge-doped fibres as a potential dosimeter. The thermoluminescence response was measured for 4 fibre types:…”
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Open circuit voltage increase of GaSb/GaAs quantum ring solar cells under high hydrostatic pressure by Montesdeoca, D., Carrington, P.J., Marko, I.P., Wagener, M.C., Sweeney, S.J., Krier, A.

“…Hydrostatic pressure can be used as a powerful diagnostic tool to enable the study of lattice dynamics, defects, impurities and recombination processes in a…”
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Growth and characterisation of Ga(NAsBi) alloy by metal–organic vapour phase epitaxy by Bushell, Z.L., Ludewig, P., Knaub, N., Batool, Z., Hild, K., Stolz, W., Sweeney, S.J., Volz, K.

“…This paper summarises results of the epitaxial growth of Ga(NAsBi) by metal–organic vapour phase epitaxy (MOVPE) and the subsequent optical and structural…”
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Recombination processes in midinfrared InGaAsSb diode lasers emitting at 2.37μm by O’Brien, K., Sweeney, S. J., Adams, A. R., Murdin, B. N., Salhi, A., Rouillard, Y., Joullié, A.

“…The temperature dependence of the threshold current of InGaAsSb∕AlGaAsSb compressively strained lasers is investigated by analyzing the spontaneous emission…”
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Theoretical and experimental analysis of 1.3-μm InGaAsN/GaAs lasers by Tomic, S., O'Reilly, E.P., Fehse, R., Sweeney, S.J., Adams, A.R., Andreev, A.D., Choulis, S.A., Hosea, T.J.C., Riechert, H.

“…We present a comprehensive theoretical and experimental analysis of 1.3- mu m InGaAsN/GaAs lasers. After introducing the 10-band k . p Hamiltonian which…”
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MOVPE growth and characterization of quaternary Ga(PAsBi)/GaAs alloys for optoelectronic applications by Nattermann, L., Ludewig, P., Knaub, N., Rosemann, N.W., Hepp, T., Sterzer, E., Jin, S.R., Hild, K., Chatterjee, S., Sweeney, S.J., Stolz, W., Volz, K.

“…[Display omitted] •Calculation of band gap and spin-orbit split-off energies of Ga(PAsBi) for different compositions.•Temperature-dependent PL and comparison…”
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A quantitative study of radiative, Auger, and defect related recombination processes in 1.3-μm GaInNAs-based quantum-well lasers by Fehse, R., Tomic, S., Adams, A.R., Sweeney, S.J., O'Reilly, E.P., Andreev, A., Riechert, H.

“…By measuring the spontaneous emission (SE) from normally operating similar to 1.3- mu m GaInNAs-GaAs-based lasers we have quantitatively determined the…”
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Drosophila sticky/citron kinase is a regulator of cell-cycle progression, genetically interacts with Argonaute 1 and modulates epigenetic gene silencing by Sweeney, S.J, Campbell, P, Bosco, G

“…The sticky/citron kinase protein is a conserved regulator of cell-cycle progression from invertebrates to humans. While this kinase is essential for completion…”
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Thermal Characteristics of 1.55- \mum InGaAlAs Quantum Well Buried Heterostructure Lasers by Sayid, S.A., Marko, I.P., Cannard, P.J., Xin Chen, Rivers, L.J., Lealman, I.F., Sweeney, S.J.

“…We have investigated the threshold current I th and differential quantum efficiency as the function of temperature in InGaAlAs/InP multiple quantum well (MQWs)…”
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The Importance of Recombination via Excited States in InAs/GaAs [Formula Omitted]m Quantum-Dot Lasers by Crowley, M.T, Marko, I.P, Masse, N.F, Andreev, A.D, Tomic, S, Sweeney, S.J, O'Reilly, E.P, Adams, A.R

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Challenges for Room Temperature Electrically Injected GeSn Semiconductor Lasers by Ellis, A., Duffy, D.A., Marko, I.P., Acharya, S., Du, W., Yu, S. Q-., Sweeney, S.J.

“…A group IV-based laser offers the possibility of fully CMOS compatible growth of integrated circuits for Si photonics. In this work, we use hydrostatic…”
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The temperature dependence of 1.3- and 1.5-μm compressively strained InGaAs(P) MQW semiconductor lasers by Phillips, A.F., Sweeney, S.J., Adams, A.R., Thijs, P.J.A.

“…We have studied experimentally and theoretically the spontaneous emission from 1.3- and 1.5- mu m compressively strained InGaAsP multiple-quantum-well lasers…”
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The Importance of Recombination via Excited States in InAs/GaAs $\hbox{1.3}\;\mu$m Quantum-Dot Lasers by Crowley, M.T., Marko, I.P., Masse, N.F., Andreev, A.D., Tomic, S., Sweeney, S.J., O'Reilly, E.P., Adams, A.R.

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Recombination and loss mechanisms in low-threshold InAs-GaAs 1.3-/spl mu/m quantum-dot lasers by Marko, I.P., Adams, A.R., Sweeney, S.J., Mowbray, D.J., Skolnick, M.S., Liu, H.Y., Groom, K.M.

“…We show that even in quantum-dot (QD) lasers with very low threshold current densities (J/sub th/=40--50 A/cm/sup 2/ at 300 K), the temperature sensitivity of…”
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