1,720,981 research outputs found
Growth of laser host thin-film optical waveguides by pulsed laser deposition
No full textOptical waveguides of laser gain media are highly desirable because the high intensity-length product and good pump-signal mode overlap, which can be achieved in the waveguide geometry, leads to a reduced threshold pump power as compared to bulk lasers. Pulsed laser deposition (PLD) has emerged as a viable means of depositing epitaxial thin films of the correct composition. We report here the deposition of GGG and YGG thin films on YAG substrates and the deposition of sapphire on sapphire substrates
Pulsed laser deposition of KNbO<sub>3</sub>
No full textThe Handbook of Thin Film Deposition is a comprehensive reference focusing on thin film technologies and applications used in the semiconductor industry and the closely related areas of thin film deposition, thin film micro properties, photovoltaic solar energy applications, new materials for memory applications and methods for thin film optical processes. In a major restructuring, this edition of the handbook lays the foundations with an up-to-date treatment of lithography, contamination and yield management, and reliability of thin films. The established physical and chemical deposition processes and technologies are then covered, the last section of the book being devoted to more recent technological developments such as microelectromechanical systems, photovoltaic applications, digital cameras, CCD arrays, and optical thin films.• A practical survey of thin film technologies aimed at engineers and managers involved in all stages of the process: design, fabrication, quality assurance and applications. • Covers core processes and applications in the semiconductor industry and new developments in the photovoltaic and optical thin film industries. • The new edition takes covers the transition taking place in the semiconductor world from Al/SiO2 to copper interconnects with low-k dielectrics.• Written by acknowledged industry experts from key companies in the semiconductor industry including Intel and IBM.• Foreword by Gordon E. Moore, co-founder of Intel and formulator of the renowned ‘Moore’s Law’ relating to the technology development cycle in the semiconductor industry
Growth of crystalline Gd<sub>3</sub>Ga<sub>5</sub>O<sub>12</sub> thin-film optical waveguides by pulsed laser deposition
No full textCrystalline and stoichiometric thin film of Gd3Ga5O12, have been deposited onto heated Y3Al5O12, substrates by a pulsed laser deposition technique. The refractive indices of the films are in excellent agreement with the bulk crystal
Pulsed-laser deposition of Ga-La-S chalcogenide glass films for optical waveguide applications
No full textThin films of Ga-La-S chalcogenide glass have been ablatively deposited onto a range of substrates, including CaF2, and microscope cover slips. The resultant films are deficient in their sulphur composition by approximately 25%, when compared to the bulk targets used, but the interesting chalcogenide photostructural effects are not compromised by this deficiency. Experiments so far have established that photorefractive effects, such as photodoping, photobleaching and grating formation. all occur readily in the thin films, and gratings have been written using laser and e-beam addressing, to create diffractive structures for optical waveguide applications
A Ti:sapphire planar waveguide laser grown by pulsed laser deposition
No full textThis paper documents the lasing performance of a waveguiding layer of Ti:sapphire, of ~12µm thickness, grown by pulsed laser deposition from a 0.12 wt % Ti2O3 Ti:sapphire single crystal target onto an undoped z-cut sapphire substrate. Lasing around 800nm is observed, when the waveguide layer is pumped by an argon ion laser, running on all blue green lines, with an absorbed power threshold of 0.56W using high reflectivity (R>98%) mirrors. Using a 5% pump duty cycle and a T = 35% output coupler, a slope efficiency of 26% with respect to absorbed power is obtained, giving quasi-CW output powers in excess of 350mW
Performance of a low loss pulsed laser deposited Nd:Gd<sub>3</sub>Ga<sub>5</sub>O<sub>12</sub> waveguide laser at 1.06µm and 0.94µm
No full textWe report the laser performance of a low propagation loss neodymium doped Gd3Ga5O12 (Nd:GGG) waveguide fabricated by pulsed laser deposition. An 8µm thick crystalline Nd:GGG film grown on an undoped Y3Al5O12 (YAG) substrate lases at 1.060µm and 1.062µm, when pumped by a Ti:sapphire laser operating at 740nm or 808nm. Using a 2.2% output coupler a 1060nm laser threshold of 4mW and a slope efficiency of 20% were observed. Laser action has also been achieved, we believe for the first time in Nd:GGG, on the quasi-three level 937nm transition. With a 2% output coupler at this wavelength a laser threshold of 17mW and a 20% slope efficiency were obtained. This demonstration of low propagation loss combined with the fact that these waveguides have a very high numerical aperture, make pulsed laser deposited thin films attractive for high power diode pumped devices
Pulsed laser deposition of KNbO<sub>3</sub> thin films
No full textThe laser ablation of stationary KNbO3 single crystal targets induces a Nb enrichment of the target surface. In rotated targets this effect is observed only in those areas irradiated with low laser fluence. The composition of the plasma formed close to the target surface is congruent with the target composition; however, at further distances K-deficient films are formed due to the preferential backscattering of K in the plasma. This loss may be compensated for by using K-rich ceramic targets. Best results so far have been obtained with [K]/[Nb] = 2.85 target composition, and crystalline KNbO3 films are formed when heating the substrates to 650 °C. Films formed on (100)MgO single crystals are usually single phase and oriented with the (110) film plane parallel to the (100) substrate surface. (100)NbO may coexist with KNbO3 on (100)MgO. At substrate temperatures higher than 650 °C, niobium diffuses into MgO forming Mg4Nb2O9 and NbO, leading to K evaporation from the film. Films formed on (001) alpha-Al2O3 (sapphire) show the coexistence of (111), (110), and (001) orientations of KNbO3, and the presence of NbO2 is also observed. KNbO3 films deposited on (001)LiNbO3 crystallize with the (111) plane of the film parallel to the substrate surface. For the latter two substrates the Nb diffusion into the substrate is lower than in MgO and consequently the K concentration retained in the film is comparatively larger
A low-loss waveguide laser grown by pulsed laser deposition
No full textWe report the fabrication of a low propagation loss (<1dB/cm) Nd:GGG waveguide by pulsed laser deposition. Using a 2% output coupler a 1.06µm laser threshold of 4mW and slope efficiency of 20% was observed
- …
