160,845 research outputs found
A 11.5 W Yb:YAG planar waveguide fabricated via pulsed laser deposition
No full textDataset for the figures in Grant-Jacob, James A, Beecher, Stephen J, Parsonage, Tina L, Hua, Ping, Mackenzie, Jacob I, Shepherd, David P and Eason, Robert W (2015) An 11.5 W Yb:YAG planar waveguide laser fabricated via pulsed laser deposition. Optical Materials Express
Data collection method: Optical spectrum analyzer (Ando AQ6317).</span
Dataset for Yb:YAG planar waveguide lasers grown by pulsed laser deposition: 70% slope efficiencies at 16 W of output power
No full textData for the figures in the paper "Beecher, S.J., Grant-Jacob, J.A., Parsonage, T.L., Hua, P., Mackenzie, J.I., Shepherd, D.P. and Eason, R.W. (2016) Yb:YAG planar waveguide lasers grown by pulsed laser deposition: 70% slope efficiencies at 16 W of output power. In, Solid State Lasers XXV: Technology and Devices, San Francisco, US, 13 - 18 Feb 2016. (doi:10.1117/12.2220388)."</span
Pulsed laser deposition of doped sesquioxide films for planar waveguide lasers
No full textThe sesquioxides Y2O3, Lu2O3 and Sc2O3 have been identified as promising laser host materials due to their excellent thermo-mechanical properties and ability to be doped with rare-earth ions. However, crystals of these materials are problematic to grow due to their high melting points of ~2500°C, which means standard methods of crystal growth from a melt need to be modified to deal with such high temperatures and become more expensive. Pulsed laser deposition (PLD) has the capability to grow these materials, without requiring a melt of material to grow from. Sintered ceramic targets of the sesquioxides, often doped with rare-earth ions, are ablated with a UV laser pulse and material is ejected. This plume of material travels through a vacuum chamber to a carefully chosen substrate where material is deposited and forms a crystalline film.Planar waveguide lasers are structures of interest due to their low lasing thresholds in comparison to bulk material, owing to the greater overlap of the pump and laser modes, and their large aspect ratio that allows efficient heat removal from the laser crystal. This, combined with the high thermal conductivity of the sesquioxides, should allow for power scaling of these waveguide lasers with minimal thermal affects. The laser results in this thesis are for progressively higher powers, and no detrimental heating affects are witnessed.This thesis reports on the growth of single and multilayer sesquioxide waveguides grown by PLD, including growth optimisation, sample analysis and laser experiments. The first sample of this project to be successfully lased was a single layer Tm:Y2O3 waveguide on a YAG substrate, which produced a maximum output power of 35 mW with 9% slope efficiency at a wavelength of 1.95 µm, and, to the best of our knowledge, was the first Tm:Y2O3 planar waveguide laser. Next, Yb:Y2O3 was the material of choice and a multilayer sample was fabricated, where the Yb:Y2O3 core was sandwiched between two undoped Y2O3 layers, again on a YAG substrate. Laser experiments with this waveguide gave a maximum output power of 1.2 W at 1030 nm, with a slope efficiency of 20%. The highest laser output power of any of the doped sesquioxide waveguides in this project is 8.5 W, achieved using a Yb:Lu2O3 sample
Diamond Hill Methodist Church parsonage
No full textDiamond Hill Methodist Church parsonage (left to right) J. F. Mitcham, Reverend W. M. Bowden, pastor; Mrs. J. C. Davis, W. W. Ward (seated in front) and W. L. Hightower, all seen sitting down on a porch outside engaging in conversation.https://mavmatrix.uta.edu/specialcollections_startelegram1940s/10265/thumbnail.jp
An 11.5 W Yb:YAG planar waveguide laser fabricated via pulsed laser deposition
No full textWe present details of the homo-epitaxial growth of Yb:YAG onto a <100> oriented YAG substrate by pulsed laser deposition. Material characterization and initial laser experiments are also reported, including the demonstration of laser action from the 15 µm-thick planar waveguide generating 11.5 W of output power with a slope efficiency of 48%. This work indicates that under appropriate conditions, high-quality single-crystal Yb:YAG growth via pulsed laser deposition is achievable with characteristics comparable to those obtained via conventional crystal growth techniques
Prof. Th. W. Adorno and the author Hans Erich Nossack.
No full textProf. Th. W. Adorno and the author Hans Erich Nossack at a reception of Insel Verlag, Buchmesse Frankfurt 1966LB
Diode-end-pumped 1.2W Yb:Y<sub>2</sub>O<sub>3</sub> planar waveguide laser
No full textFabrication, characterization and laser performance of a Watt level ytterbium-doped yttria waveguide laser is presented. The waveguide was grown onto a YAG substrate by pulsed laser deposition and features a 6 µm thick ytterbium-doped yttria layer sandwiched between two 3 µm undoped yttria layers. The laser deposited film was characterized by X-ray diffraction, showing a high degree of crystallinity and analyzed spectroscopically, showing performance indistinguishable from previously reported bulk material. When pumped with 8.5 W from a broad area diode laser the waveguide laser produces 1.2 W of output at 1030 nm
Pulsed laser deposition of Yb:Y<sub>2</sub>O<sub>3</sub> planar waveguide lasers
No full textRare earth-doped sesquioxides, particularly yttria (Y2O3), scandia (Sc2O3) and lutetia (Lu2O3), are very promising materials for high power laser applications due to their excellent combination of thermal, optical and spectroscopic properties. These simple cubic crystals have been successfully doped with rare earth elements such as Yb, Tm and Er, but are challenging to grow as bulk crystals, due to their high melting points (~2400°C).Using pulsed laser deposition, we have grown both single and multilayer Yb-doped crystalline yttria waveguides on 1 cm2 YAG substrates. A multilayer sample with a 3 µm Y2O3 layer either side of a 6 µm Yb:Y2O3 doped region gave a maximum output power of 1.2 W at 1030 nm, for ~10.5 W of diode pump power. This waveguide design provides significantly higher gain for the fundamental waveguide mode than for higher order modes, enabling efficient multimode pumping whilst favouring diffraction limited output. The maximum observed slope efficiency was 22% (with respect to absorbed power), using a simple quasi-monolithic plane-plane resonator cavity with a 30%R output coupler. With no active cooling, even at these high pump powers, no sign of thermal effects in the waveguide have been observed, confirming the excellent thermal properties of this material.We will discuss these first results together with further experiments that will be performed with an optimised cavity length to achieve higher output power, lower threshold and greater slope efficiency
The English parsonage in the early nineteenth century
No full textA detailed illustrated history of the development of the English parsonage from 1811 up to around 1850, focusing in particular on the impact of A. W. N. Pugin and the gothic revival on late Georgian architecture. Illustrated with extensive new photography by Martin Charles (Full Text Available via URL below
M.E. Church and parsonage exterior
No full textA color postcard depicting M.E. Church and Parsonage in Georgetown, Delaware, a large brick church with a tall bell tower. Miss Mabel Johnson of Philadelphia, Pennsylvania, received this postcard from Ella. Ella wrote that she was glad Mabel arrived all right with the loud kitten and gorgeous bouquet. Ella told Mabel she had heard from Mr. B and that W. S. was building something for them. Marshall & Chipman published the postcard. The postcard was printed in Germany. A postmark on the back indicates that this postcard was mailed from Georgetown, Delaware. The postage stamp is a one-cent U.S. #300, Benjamin Franklin. The back of the postcard is labeled 30.00 and 0243
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