Results 271 to 280 of about 30,451 (313)

Helical distributed feedback Gaslaser

1983 Eighth International Conference on Infrared and Millimeter Waves, 1982
Theory, realization and mode characteristics of a helical distributed feedback far-ir gas laser are presented. In this laser DFB is provided by a structure of helical symmetry contrary to standard DFB lasers which are based on linear periodic modulations.
H.P. Preiswerk, G. Küttel, F.K. Kneubühl   +2 more
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InGaAsP distributed-feedback multi-quantum-well lasers

Conference on Lasers and Electro-Optics, 1986
The fabrication and performance characteristics of 1.3 μm InGaAsP distributed feedback (DFB) lasers with multiquantum well (MQW) active layers are reported. The lasers are of the double channel planar buried heterostructure type and utilize a second order grating with a periodicity of ∼3900 Å for frequency selective feedback.
N. K. Dutta, S. G. Napholtz, A. B. Piccirilli, G. Przybylek   +3 more
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Distributed-Feedback Semiconductor Lasers

1986
We have seen in Chapter 6 that a conventional semiconductor laser does not emit light in a single longitudinal mode. In general, the mode closest to the gain peak is most intense, and a few percent of the output power is carried by other longitudinal modes lying close to the gain peak.
Govind P. Agrawal, Niloy K. Dutta
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Distributed Feedback Lasers Based on MAPbBr₃

Advanced Materials Technologies, 2018
AbstractHybrid perovskite semiconductors hold great promise as low‐cost, yet high performance gain media for lasers. Distributed feedback (DFB) resonator structures are a key to unlock low laser threshold levels, which are essential on the way to the first electrically operated perovskite laser diode.
Neda Pourdavoud, André Mayer, Maximilian Buchmüller, Kai Brinkmann, Tobias Häger, Ting Hu, Ralf Heiderhoff, Ivan Shutsko, Patrick Görrn, Yiwang Chen, Hella‐Christin Scheer, Thomas Riedl   +11 more
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Semiconducting polymer distributed feedback lasers

Applied Physics Letters, 1998
We have fabricated photopumped distributed feedback lasers by spin-casting thin films of the semiconducting polymer poly(2-butyl, 5-(2′-ethyl-hexyl)-1,4-phenylenevinylene) over gratings in silicon oxide. The lasers have two modes that each have a linewidth of 0.2 nm.
M. D. McGehee, M. A. Dı́az-Garcı́a, F. Hide, R. Gupta, E. K. Miller, D. Moses, A. J. Heeger   +6 more
openaire   +1 more source

Quasi-periodic distributed feedback laser

Nature Photonics, 2010
Although lasers have found numerous applications, their design is often still based on the concept of a gain medium within a mirror cavity. Exceptions to this are distributed feedback lasers(1), in which feedback develops along a periodic structure, or random lasers, which do not require any form of cavity(2).
Lukas Mahler, Alessandro Tredicucci, Fabio Beltram, Christoph Walther, Jérôme Faist, Harvey E Beere, David A Ritchie, Diederik S Wiersma   +7 more
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Gain saturation in distributed feedback lasers

Applied Optics, 1975
An approximate method is presented for the analysis of overcoupled distributed feedback lasers. A closed form expression is obtained for the power emitted by a laser normalized to the saturation power in terms of the loss coefficient alpha(L), small signal gain coefficient alpha(0), coupling parameter kappa, and length of the laser L.
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Lasers with distributed feedback (review)

Soviet Journal of Quantum Electronics, 1975
A review is given of the published literature and the work carried out by the present authors on distributedfeedback lasers, in which optical-frequency electromagnetic oscillations are generated using structures with spatially periodic inhomogeneities (of dimensions comparable with the emission wavelength).
V N Luk'yanov, A T Semenov, N V Shelkov, S D Yakubovich   +3 more
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Distributed feedback laser in CdS

1974 International Electron Devices Meeting (IEDM), 1974
Distributed feedback laser was observed in CdS with a simple DFB structure under electron beam excitation. The lasing characteristics such as the temperature dependence and the time dependence of the laser were examined. The line width of the laser spectrum was found to be less than 0.8 A.
Y.Aoyagi, S.Namba
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Excimer laser pumped distributed feedback dye laser

Optics Communications, 1987
Abstract Single pulse emission of excimer laser pumped distributed feedback dye laser (DFDL) is demonstrated for the first time. Stable 80 ps long single pulses are generated by quenching an overpumped DFDL. The light of the quenched DFDL and the quencher laser are different in polarization.
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