Building Blocks for Time-Resolved Laser Emission in Mid-Infrared Quantum Well Lasers PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Building Blocks for Time-Resolved Laser Emission in Mid-Infrared Quantum Well Lasers PDF full book. Access full book title Building Blocks for Time-Resolved Laser Emission in Mid-Infrared Quantum Well Lasers by Gabriel D. Mounce. Download full books in PDF and EPUB format.
Author: Gabriel D. Mounce
Publisher:
ISBN: 9781423504252
Category :
Languages : en
Pages : 107
Get Book Here
Book Description
The objective of this research is to improve the performance of mid- infrared semiconductor quantum-well lasers. Lasers operating in the mid-infrared are useful for many Air Force applications which include infrared (IR) countermeasures in particular. Countermeasure applications require lasers that are compact, and able to emit at high powers while operating at room temperature. Limits to power increases are seen in the transverse modal development of laser oscillation. These modes typically form in the waveguiding active region contributing to the laser output. However, competing modes outside of this region also develop when the confining structural layers have the right characteristics. These competing modes may draw power away from the main lasing mode, causing efficiency to drop. Therefore, theoretical models indicate that these "ghost" modes should be extinguished. The goal of this work is to incorporate antimony-based semiconductor laser devices into a time-resolved photoluminescence (TRPL) experiment to examine modal development immediately after excitation. TRPL utilizes a non-linear wave mixing technique known as frequency upconversion to resolve sub-picosecond luminescence occurrences after excitation. Modification to the experiment is performed to produce laser emission from five mid-IR semiconductor laser samples. Both spontaneous and stimulated emission spectra are recorded. Alignment of the experiment is also carried out to produce upconversion of the PL signal to prepare for the incorporation of laser emission.
Author: Gabriel D. Mounce
Publisher:
ISBN: 9781423504252
Category :
Languages : en
Pages : 107
Get Book Here
Book Description
The objective of this research is to improve the performance of mid- infrared semiconductor quantum-well lasers. Lasers operating in the mid-infrared are useful for many Air Force applications which include infrared (IR) countermeasures in particular. Countermeasure applications require lasers that are compact, and able to emit at high powers while operating at room temperature. Limits to power increases are seen in the transverse modal development of laser oscillation. These modes typically form in the waveguiding active region contributing to the laser output. However, competing modes outside of this region also develop when the confining structural layers have the right characteristics. These competing modes may draw power away from the main lasing mode, causing efficiency to drop. Therefore, theoretical models indicate that these "ghost" modes should be extinguished. The goal of this work is to incorporate antimony-based semiconductor laser devices into a time-resolved photoluminescence (TRPL) experiment to examine modal development immediately after excitation. TRPL utilizes a non-linear wave mixing technique known as frequency upconversion to resolve sub-picosecond luminescence occurrences after excitation. Modification to the experiment is performed to produce laser emission from five mid-IR semiconductor laser samples. Both spontaneous and stimulated emission spectra are recorded. Alignment of the experiment is also carried out to produce upconversion of the PL signal to prepare for the incorporation of laser emission.
Author: Gabriel D. Mounce
Publisher:
ISBN:
Category : Lasers
Languages : en
Pages :
Get Book Here
Book Description
Author: Steven M. Gorski
Publisher:
ISBN: 9781423509721
Category : Hot carriers
Languages : en
Pages : 93
Get Book Here
Book Description
Research in mid-infrared laser technology has uncovered numerous applications for commercial and government use. A limiting factor for mid- infrared semiconductors is nonradiative recombination, which is a process that produces excess heat without emitting a photon. Nonradiative recombination mechanisms occur over a short time period and difficult to measure. Growth methods have significantly reduced the nonradiative recombination in some materials. The objective of this research is to further the understanding of how quantum well structures impact carrier recombination. InAsSb/InAlASb and InAs/ GaInSb quantum well structures were studied with time-resolved photoluminescence utilizing upconversion, a non-linear wave mixing technique. This research reports Shockley-Read-Hall, radiative, and Auger recombination coefficients at 77k. The luminescence rise times of type I and type II structures are also compared. The number of states available within the quantum well was found to dictate how quickly carriers were able to recombine radiatively. Finally, spectral data was taken to examine the spectral decay of the luminescence. Carrier temperatures were extracted from the spectral data. Type I structures were found to have hotter carrier temperatures and higher Auger coefficients than type II structures.
Author: Peter S. Zory
Publisher: Academic Press
ISBN: 9780127818900
Category : Science
Languages : en
Pages : 530
Get Book Here
Book Description
Provides information on all aspects of QW lasers, from the basic mechanism of optical gain, through the current technological state of the art, to the future technologies of quantum wires and quantum dots. Those working with lasers, especially semiconductor lasers, should find the book useful.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 25
Get Book Here
Book Description
This report summarizes the entire research period. In this program, we performed experiments using a femtosecond mid-infrared pump-probe system implemented for QCL samples operating at 4.6 and 5.3 m. We employed femtosecond time-resolved pump-probe measurements to probe the nature of the transport through the laser structure via the dynamics of the gain. The gain recovery was determined by the time-dependent transport of electrons through the cascade heterostructure; as the laser approaches and exceeds threshold, the gain recovery shows a dramatic reduction due to the onset of quantum stimulated emission. Since the electron transport through each state in the cascade is determined by the state lifetime, the transport in a cascade laser is driven by the photon density in the cavity. The gain recovery is qualitatively different from that in conventional atomic, molecular and interband semiconductor lasers due to the superlattice transport in the cascade. We also studied the effects of pulse propagation in the laser, including group velocity dispersion and coherent pulse reshaping due to ultrafast Rabi flopping of the gain medium.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 37
Get Book Here
Book Description
This report results from a contract tasking A.F.loffe Physical-Technical Institute as follows: High-power mid-infrared semiconductor lasers are of great importance for many applications such as laser diode spectroscopy, pollution monitoring low-loss optical communication medical diagnostics, etc. This project will introduce quantum wells into a heterojunction structure, as a means of obtaining near-room-temperature, high power mid-IR laser sources. Both experimental performance and means of fabrication will be investigated.
Author: Michael R. McKay
Publisher:
ISBN: 9781423527138
Category : Photoluminescence
Languages : en
Pages : 80
Get Book Here
Book Description
In the world of semiconductor photonic device fabrication, one important objective may be to extract as much light as possible from the device. In these devices, photons are created when electrons recombine with holes by transitioning from a high-energy state to a lower one. Unfortunately, electron- hole recombination does not always result in the formation of a photon. There are three basic types of recombination: the first results in the formation of a photon and is called radiative recombination; and the second and third, known as Shockley-Read-Hall and Auger recombination, result in the heating of the device and do not produce photons and are therefore called non-radiative recombination. All three processes occur simultaneously in a device, and either a radiative or non-radiative recombination coefficient can be associated with the relative rate of each. The lifetime of an electron in a high-energy state is so small, on the order of nanoseconds, that there is no way to measure these coefficients directly. However, sum frequency generation is a technique to indirectly measure these coefficients by taking advantage of the speed of light to resolve these processes in time. From the resulting data, these recombination coefficients can be extracted.
Author: Leslie G. Vaughn
Publisher:
ISBN:
Category : Molecular beam epitaxy
Languages : en
Pages : 352
Get Book Here
Book Description
Author: Eli Kapon
Publisher: Academic Press
ISBN: 0080540929
Category : Science
Languages : en
Pages : 467
Get Book Here
Book Description
This book covers the device physics of semiconductor lasers in five chapters written by recognized experts in this field. The volume begins by introducing the basic mechanisms of optical gain in semiconductors and the role of quantum confinement in modern quantum well diode lasers. Subsequent chapters treat the effects of built-in strain, one of the important recent advances in the technology of these lasers, and the physical mechanisms underlying the dynamics and high speed modulation of these devices. The book concludes with chapters addressing the control of photon states in squeezed-light and microcavity structures, and electron states in low dimensional quantum wire and quantum dot lasers. The book offers useful information for both readers unfamiliar with semiconductor lasers, through the introductory parts of each chapter, as well as a state-of-the-art discussion of some of the most advanced semiconductor laser structures, intended for readers engaged in research in this field. This book may also serve as an introduction for the companion volume, Semiconductor Lasers II: Materials and Structures, which presents further details on the different material systems and laser structures used for achieving specific diode laser performance features. - Introduces the reader to the basics of semiconductor lasers - Covers the fundamentals of lasing in semiconductors, including quantum confined and microcavity structures - Beneficial to readers interested in the more general aspects of semiconductor physics and optoelectronic devices, such as quantum confined heterostructures and integrated optics - Each chapter contains a thorough introduction to the topic geared toward the non-expert, followed by an in-depth discussion of current technology and future trends - Useful for professionals engaged in research and development - Contains numerous schematic and data-containing illustrations
Author: Harvey C. Hoch
Publisher: Cambridge University Press
ISBN: 9780521462648
Category : Medical
Languages : en
Pages : 448
Get Book Here
Book Description
The book also aims to stimulate innovative, productive interactions among materials scientists, engineers, and biologists, and to explore ways in which materials scientists and engineers can exploit biological principles and biological assemblies to produce new and ever smaller devices.
