Download or read book Near diffraction limited High power Pulsed and CW Antiguided Semiconductor Laser Arrays written by Haiquan Yang and published by . This book was released on 1999 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In plane Semiconductor Lasers written by and published by . This book was released on 1999 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 2 d Coherent Power Scaling of Mid infrared Quantum Cascade Lasers written by Christopher Andrew Sigler and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scaling the continuous-wave (CW) power of quantum cascade lasers (QCLs) beyond ~5 W has proven difficult, and beam-quality degradation is common when scaling the device volume for high power. The primary objective of this work was to develop methods for spatially-coherent power scaling of mid-infrared-emitting QCLs to high CW powers. Two approaches were investigated: 1) resonant leaky-wave-coupled antiguided phase-locked laser arrays; and 2) grating-coupled surface-emitting lasers (GCSELs). These two approaches can be combined to realize high surface-emitted powers in a spatially and temporally coherent beam pattern. Optical and thermal models of planarized leaky-wave-coupled phase-locked QCL arrays were coupled together to investigate the influence of thermal lensing on modal behavior. Self-focusing under thermally-induced index variations across the array were found to impact the field profile and promote multi-moding due to gain spatial hole burning. Two techniques were found to mitigate this effect: 1) employing anti-resonant reflective-optical waveguide terminations outside the array; and 2) chirping the element width across the array to obtain identical optically-equivalent widths under CW operation, eliminating thermal lensing at a particular operating condition. Five-element phase-locked arrays of 4.7 μm-emitting QCLs were demonstrated which operate in a near-diffraction-limited beam (primarily in the in-phase array mode) to 5.1 W peak pulsed power, in agreement with simulations. Spectrally resolved near- and far-field measurements indicate that the wide spectral bandwidth of the QCL core promotes multi-mode operation at high drive levels. An optimized array design was identified to allow sole in-phase mode operation to high drive levels above threshold, indicating that full spatial coherence to high output powers does not require full temporal coherence for phase-locked laser arrays. Lastly, a novel method for obtaining a single-lobed beam pattern from transverse magnetic (TM)-polarized GCSELs is proposed: resonant coupling of the optical mode of a QCL to the antisymmetric surface plasmon mode of a 2nd-order distributed feedback metal/semiconductor grating results in strong antisymmetric-mode absorption. Lasing in the symmetric mode, resulting in a single-lobed far-field beam pattern from the substrate emission, is strongly favored around resonance. For infinite-length devices, the symmetric mode has negligible absorption loss while still being efficiently outcoupled by the grating.

Download or read book High Power Performance and Modulation of Semiconductor Lasers written by Constance J. Chang-Hasnain and published by . This book was released on 1987 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High power Near resonant 1 55 micron emitting InGaAsP InP Antiguided Diode Laser Arrays written by Arnab Bhattacharya and published by . This book was released on 1997 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Future Trends in Microelectronics written by Serge Luryi and published by John Wiley & Sons. This book was released on 2010-08-03 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the summer of 2009, leading professionals from industry, government, and academia gathered for a free-spirited debate on the future trends of microelectronics. This volume represents the summary of their valuable contributions. Providing a cohesive exploration and holistic vision of semiconductor microelectronics, this text answers such questions as: What is the future beyond shrinking silicon devices and the field-effect transistor principle? Are there green pastures beyond the traditional semiconductor technologies? This resource also identifies the direction the field is taking, enabling microelectronics professionals and students to conduct research in an informed, profitable, and forward-looking fashion.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2000 with total page 956 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Conference Proceedings written by and published by . This book was released on 1991 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Summaries of Papers Presented at the Conference on Lasers and Electro optics written by and published by . This book was released on 1998 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book LEOS 91 Conference Digest written by IEEE Lasers and Electro-Optics Society and published by . This book was released on 1991 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Power Coupled Ridge Waveguide Semiconductor Laser Arrays written by Y. Twu and published by . This book was released on 1984 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using index-guided ridge waveguide structures, we have obtained single-lobe far-field pattern from coupled multiple-stripe semiconductor laser arrays. A stable far-field pattern has been observed up to 250-mW peak pulsed power. This desired performance of a semiconductor laser array is achieved by intentional pumping of a laser array at coupling regions, which is possible in ridge waveguide structures. (Author).

Download or read book Laser Diode Technology and Applications written by and published by . This book was released on 1993 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Conference on Lasers and Electro Optics written by Optical Society of America and published by Institute of Electrical & Electronics Engineers(IEEE). This book was released on 1992 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 1860 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Semiconductor Lasers for Lightwave Communication Systems written by Society of Photo-optical Instrumentation Engineers and published by SPIE-International Society for Optical Engineering. This book was released on 2001 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Power High Beam Quality Mid infrared Quantum Cascade Lasers written by Jae Ha Ryu and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coherent power scaling of quantum cascade lasers (QCLs) for high-power, single-mode continuous-wave (CW) operation has proven to be quite a difficult task - while the device volume could be scaled for higher output power, many other factors such as beam quality and thermal resistance are negatively impacted if the device design is not carefully considered. The main objective of this work has been to develop methods for realizing high continuous-wave (CW) output power QCLs with high beam quality and minimal beam steering. One attractive approach for tackling this problem is the use of resonant leaky-wave-coupled antiguided phase-locked laser arrays. This dissertation focusses on two approaches to achieve high coherent power: 1) one alternate to the resonant leaky-wave-coupled antiguided phase-locked array concept, so called 'reverse-taper'laser; and 2) one combining grating-coupled surface-emitting lasers (GCSELs) with resonant leaky-wave-coupled antiguided phase-locked arrays, where each array element is coupled in both the lateral and longitudinal direction; thus, has a potential for multi-watt -CW surface-emitted output powers with good beam quality and narrow spectral linewidth. The novel geometry reverse-taper QCL device can scale the output power while maintaining good beam quality and beam stability - the tapered region scales the output power, while the emitting facet is located at the narrow-end taper section, which provides mode filtering by suppressing high-order spatial modes. A small degree of collimated-beam centroid movement (