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Author : Iman Kundu
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (118 download)
Download or read book Frequency Tunable Terahertz Quantum Cascade Lasers written by Iman Kundu and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Tasmim Alam
Publisher : Cuvillier Verlag
ISBN 13 : 3736962975
Total Pages : 132 pages
Book Rating : 4.7/5 (369 download)
Download or read book Spectroscopic Applications of Terahertz Quantum-Cascade Lasers written by Tasmim Alam and published by Cuvillier Verlag. This book was released on 2020-10-29 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum cascade lasers (QCLs) are attractive for high-resolution spectroscopy because they can provide high power and a narrow linewidth. They are particularly promising in the terahertz (THz) range since they can be used as local oscillators for heterodyne detection as well as transmitters for direct detection. However, THz QCL-based technologies are still under development and are limited by the lack of frequency tunability as well as the frequency and output power stability for free-running operation. In this dissertation, frequency tuning and linewidth of THz QCLs are studied in detail by using rotational spectroscopic features of molecular species. In molecular spectroscopy, the Doppler eff ect broadens the spectral lines of molecules in the gas phase at thermal equilibrium. Saturated absorption spectroscopy has been performed that allows for sub-Doppler resolution of the spectral features. One possible application is QCL frequency stabilization based on the Lamb dip. Since the tunability of the emission frequency is an essential requirement to use THz QCL for high-resolution spectroscopy, a new method has been developed that relies on near-infrared (NIR) optical excitation of the QCL rear-facet. A wide tuning range has been achieved by using this approach. The scheme is straightforward to implement, and the approach can be readily applied to a large class of THz QCLs. The frequency and output stability of the local oscillator has a direct impact on the performance and consistency of the heterodyne spectroscopy. A technique has been developed for a simultaneous stabilization of the frequency and output power by taking advantage of the frequency and power regulation by NIR excitation. The results presented in this thesis will enable the routine use of THz QCLs for spectroscopic applications in the near future.
Author : Yifan Jiang (Ph. D. in electrical and computer engineering)
Publisher :
ISBN 13 :
Total Pages : 204 pages
Book Rating : 4.:/5 (111 download)
Download or read book Broadly Tunable Terahertz Difference Frequency Generation in Mid-infrared Quantum Cascade Lasers written by Yifan Jiang (Ph. D. in electrical and computer engineering) and published by . This book was released on 2017 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Room-temperature terahertz (THz) sources analogous to diode lasers in the near-infrared/visible or quantum cascade lasers (QCL) in the mid-infrared (mid-IR), i.e., electrically pumped, compact, widely tunable, and suitable for low-cost production, are highly desired for feasible and inexpensive THz systems. This dissertation focuses on demonstrating broadly tunable, room-temperature THz systems based on intra-cavity difference frequency generation (DFG) in mid-IR QCLs with improved spectral capability for versatile applications. Spectral control using an external cavity provides the widest tuning range and is favored for real-world applications. DFG-THz could be spectrally tuned by either tuning one mid-IR pump or by tuning both mid-IR pumps together. I built a Littrow-type, external cavity THz DFG-QCL system that generated spectral tunable THz radiation by fixing one mid-IR pump frequency with an integrated DFB grating on top of the QCL structure and tuning the other mid-IR pump frequency with an external grating, thus demonstrating record broadband narrow linewidth THz frequency tuning from 1.2 to 5.9 THz. A Cherenkov waveguide is used in this system to extract THz radiation through the semi-insulating InP substrate; however, InP has dispersion in 1–6 THz, resulting in steering far field profiles for different THz frequencies. Replacing the InP substrate with high-resistance silicon through an adhesive bonding process solved the beam steering problem of this THz DFG-QCL system. I also built a double-Littrow, external cavity DFG-THz system that tunes both mid-IR pump frequencies using two external diffraction gratings. Such a system allows performing a comprehensive spectroscopic study of the optical nonlinearity and its dependence on the mid-infrared pump frequencies. Our work shows that the terahertz generation efficiency can vary by a factor of two or more, depending on the spectral position of the mid-infrared pumps, even for a fixed THz difference frequency. Using this system, we investigated different active region designs: bound-to-continuum, continuum-to-continuum, three-phonon-resonance, and dual-upper-state active region design. Our studies show THz DFG-QCL based a bound-to-continuum active region with gain centered around 15 μm has an order of magnitude enhancement of mid-IR to THz conversion efficiency, which provides a trend for future improvement of the power performance of THz DFG-QCLs
Author : Nor Kamilah Binti Saat
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (857 download)
Download or read book Imaging Using an Electronically Tunable Terahertz Quantum Cascade Laser written by Nor Kamilah Binti Saat and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis studies THz frequency imaging using different electrically tunable THz QCLs as the source. The THz QCL is based on a three-well resonant phonon active region design and uses a single metal waveguide. Using a heterogeneous cascade scheme, obtained by changing the growth rate of Ga during epitaxial process, the thickness of the GaAs is reduced progressively by 10% throughout the active region. As a result, the emission frequency can be varied from 3.05 to 3.35 THz by switching the bias of the QCL. Two types of imaging system are demonstrated. First, dual frequency imaging is demonstrated by electrically tuning the QCL bias, and a transmission image of the high explosive PETN and other polycrystalline samples (i.e. lactose monohydrate, glucose monohydrate, and sucrose) at frequencies of 3.05 THz and 3.24 THz are obtained in a single raster scan of a sample. By taking the difference of the natural logarithms of the transmission, coefficients obtained at each frequency, difference- attenuation-coefficient images for the samples can be obtained. The difference- intensity imaging may also be found directly by combining amplitude modulation of the QCL bias, and hence output frequency, with lock-in detection. Owing to their unique molecular-specific absorption spectra, the samples measured could be readily distinguished using this methodology. Second, multi-frequency imaging is demonstrated by electrically tuning a heterogeneous active region QCL at five different biases, producing five different output frequencies. Using a scanning resolution target, the imaging system has been shown to be independent of the radiation wavelength, which has been explained through measurement of the far-field emission profile of the QCL. Using the imaging system, the attenuation coefficients of polycrystalline samples have been determined at five frequencies and these results compared with those obtained using THz frequency time-domain spectroscopy and Fourier transform spectroscopy.
Author : Aiting Jiang
Publisher :
ISBN 13 :
Total Pages : 204 pages
Book Rating : 4.:/5 (94 download)
Download or read book Widely Tunable Terahertz Semiconductor Laser Sources written by Aiting Jiang and published by . This book was released on 2015 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Terahertz Quantum Cascade Lasers (THz QCLs) and Terahertz Difference Frequency Generation Quantum Cascade Laser sources (DFG-QCLs) are two types of semiconductor THz radiation sources that are compact and amenable to production in mass quantities. THz QCL can generate over 1W of power under cryogenic temperatures, while THz DFG-QCL can be operated under room temperature over 1mW level output. For either case, widely tunable solution is highly desired for spectroscopy applications. For THz QCLs, operation is still limited to cryogenic temperature and broad tuning is not available. Our experimental study shows that using variable barriers is a viable approach to enhance the design space for THz QCLs. We also propose to tune the spectral output of these devices using an optically projected variable distributed feedback grating. Tuning will be achieved by changing the projected grating period. Preliminary experimental results support the idea but higher pumping light intensity is required for this method to work. For THz DFG-QCLs, very broad tuning in 1-6 THz range has been demonstrated using rotating diffraction grating in an external cavity setup. Similar tuning range can also be achieved in a monolithic configuration. Based on the previous work which demonstrated an electrical monolithic tuner with 580 GHz tuning range, we design and test in this dissertation a linear array of 10 DFG-QCL devices to cover a 2 THz tuning range. An independent gain control scheme is developed to achieve high yield (~100%) of individual device. It is implemented via independent current pumping of two electrically isolated sections. Surface DFB grating and independent current pumping scheme used in our DFG QCLs is found to be useful for mid-IR QCL array sources. We propose a longitudinal integration scheme of multiple grating sections. It enables a single ridge to emit single mode radiation at different wavelengths upon selection. This helps to reduce mid-IR QCL array far field span. We demonstrated single ridge devices that can emit 2 or 3 different wavelengths upon selection.
Author : Qi Qin (Ph. D.)
Publisher :
ISBN 13 :
Total Pages : 188 pages
Book Rating : 4.:/5 (832 download)
Download or read book Development of Tunable Terahertz Quantum Cascade Wire Lasers written by Qi Qin (Ph. D.) and published by . This book was released on 2012 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: For a long time, terahertz (THz) radiation has been of great interest to scientific community because of its spectroscopic and imaging applications based on its unique properties, such as the capabilities to penetrate many materials which are opaque in other frequency range (e.g. packaging, plastics, paints and semiconductors), and spectroscopic signatures of many important materials. In this thesis, a continuously tunable THz wire QC laser, which comprises a QC laser with deep sub-wavelength transverse dimensions, and a movable side object, termed as "plunger", is demonstrated. This deep sub-wavelength cross-section results in a large fraction of mode propagating outside of the laser core (GaAs/A10.15Ga0.85As material system). The frequency tuning is achieved by changing the transverse wave vector, using a plunger made by metal (metal plunger) or silicon (dielectric plunger). When nudged close to the wire laser core, the metal plunger can push modes to the opposite side of the waveguide. Confined by a metal-metal waveguide, the mode is squeezed and the transverse wave vector is increased, resulting in a blue-shifted frequency. In contrast, a silicon plunger can suck the mode out due to its similar refractive index to GaAs/Al0.15Ga0.85As material system of laser core. Thus a decreased transverse wave vector results in a redshifted frequency. Although a tuning record of 138GHz (3.6%) was achieved, a discontinuous tuning resulted from a jittering movement of the plungers due to its friction with the guiding system. To solve this problem, an improved plunger based on micro-mechanical system (MEMS) was implemented. This MEMS plunger uses a two-stage folded-beam flexure to isolate the misaligned external actuation. The plunger is attached with the flexure which suspends above a silicon substrate to eliminate friction. Eventually, this MEMS flexure was actuated by a mechanical system which comprised a lever to de-amplify the displacement of a linear mechanical feedthrough. This MEMS plunger enabled a restorable and frictionless movement which led to a continuous tuning range of 330GHz (8.6%) centered at ~3.85 THz. The challenges posted by the weak mode discrimination led to the development of comb-shape connectors which electrically connect the top metal of wire lasers and the side bonding pad. This design can significantly increase the mode discrimination by selectively guiding undesired mode into the lossy bonding pad. This robust design of single mode operation enables the initial lasing at a frequency far below the gain peak, which can potentially increase the tuning range significantly.
Author : Dan Botez
Publisher : Cambridge University Press
ISBN 13 : 1108570607
Total Pages : 552 pages
Book Rating : 4.1/5 (85 download)
Download or read book Mid-Infrared and Terahertz Quantum Cascade Lasers written by Dan Botez and published by Cambridge University Press. This book was released on 2023-09-14 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn how the rapidly expanding area of mid-infrared and terahertz photonics has been revolutionized in this comprehensive overview. State-of-the-art practical applications are supported by real-life examples and expert guidance. Also featuring fundamental theory enabling you to improve performance of both existing and future devices.
Author : Larry A. Coldren
Publisher : John Wiley & Sons
ISBN 13 : 1118148185
Total Pages : 752 pages
Book Rating : 4.1/5 (181 download)
Download or read book Diode Lasers and Photonic Integrated Circuits written by Larry A. Coldren and published by John Wiley & Sons. This book was released on 2012-03-02 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diode Lasers and Photonic Integrated Circuits, Second Edition provides a comprehensive treatment of optical communication technology, its principles and theory, treating students as well as experienced engineers to an in-depth exploration of this field. Diode lasers are still of significant importance in the areas of optical communication, storage, and sensing. Using the the same well received theoretical foundations of the first edition, the Second Edition now introduces timely updates in the technology and in focus of the book. After 15 years of development in the field, this book will offer brand new and updated material on GaN-based and quantum-dot lasers, photonic IC technology, detectors, modulators and SOAs, DVDs and storage, eye diagrams and BER concepts, and DFB lasers. Appendices will also be expanded to include quantum-dot issues and more on the relation between spontaneous emission and gain.
Author : Ningren Han
Publisher :
ISBN 13 :
Total Pages : 118 pages
Book Rating : 4.:/5 (868 download)
Download or read book Electrically Tunable Terahertz Quantum Cascade Lasers written by Ningren Han and published by . This book was released on 2013 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, microelectromechanical systems (MEMS) assisted electrically tunable terahertz quantum cascade lasers (THz QCLs) are designed and demonstrated. Two MEMS tuner devices are proposed to achieve electrically tunable THz QCLs. One is the electrostatic comb drive actuated tuner design and the other one is a two-stage flexure design that is actuated by an external piezo nano-positioning actuator. The MEMS tuner devices are all fabricated using standard foundry process SOIMUMPs from MEMSCAP Inc. with some additional in-house post-processings. First order distributed-feedback (DFB) THz wire QCLs with robust mode selectors are designed and fabricated at the MIT Microsystems Technology Laboratories (MTL) using processes developed at our group. By integrating the MEMS tuner chips with the THz QCL chips, broadband electrically tunable THz QCLs are successfully demonstrated. This thesis work provides an important step towards realizing turn-key tunable THz coherent sources for a variety of applications such as THz spectroscopy and THz coherent tomography.
Author : Christopher Curwen
Publisher :
ISBN 13 :
Total Pages : 96 pages
Book Rating : 4.:/5 (97 download)
Download or read book Theory and Design of Tunable Terahertz Metamaterials for Application to Tunable Terahertz Quantum Cascade Lasers written by Christopher Curwen and published by . This book was released on 2014 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Terahertz quantum cascade lasers are compact, coherent sources of THz power that have drawn considerable attention in the past 10-15 years for their potential use in THz applications such as spectroscopy and imaging. One of the key developments required to further the usefulness of THz QCLs is robust, broadband tenability. In this work, I describe a new technique for tuning THz QCLs by incorporation MEMS fixed-fixed and fixed-free cantilever beams into a THz transmission line metamaterial resonant cavity. An analytic model for such THz transmission line metamaterials is demonstrated using transmission line theory and is supported by 2-D and 3-D finite element simulations. Proposed processes for fabricating tunable THz transmission line metamaterials are outlined and current progress on actual fabrication and device testing is reported.
Author : Fan Wang (Ph. D.)
Publisher :
ISBN 13 :
Total Pages : 134 pages
Book Rating : 4.:/5 (113 download)
Download or read book New Modeling of Compact, High-efficiency, and Widely-tunable Gas-phase Terahertz Lasers written by Fan Wang (Ph. D.) and published by . This book was released on 2019 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: The terahertz region, in the heart of the electromagnetic spectrum, has been the least utilized, in part due to inadequacies of available sources. Optically pumped far-infrared (OPFIR) lasers were one of the most powerful continuous-wave terahertz sources. However, such lasers have long been thought to have intrinsically low efficiency, not tunable in frequency, and large sizes. In this thesis, we introduce a compact, frequency-tunable source of terahertz radiation with high efficiency. We first present both an innovative theoretical model and experimental validation of a Methyl Fluoride OPFIR laser at 0.25 THz that exhibits 10x greater efficiency and 1,000x smaller volume than the best commercial lasers. Unlike previous OPFIR-laser models involving only a few energy levels that failed even qualitatively to match experiments at high pressures, our ab-initio theory matches experiments quantitatively, within experimental uncertainties with no free parameters, by accurately capturing the interplay of millions of degrees of freedom in the laser. Moreover, we demonstrate a widely frequency-tunable compact terahertz radiation with laughing gas (nitrous oxide N2O) pumped by a quantum cascade laser (QCL). In experiments, broad tunability is achieved over 31 lines spanning 0.25-0.80 THz, each with kilohertz linewidths. Our comprehensive theoretical model is able to constrain the key molecular parameters and predict the optimal performance of the laser. The concept of QCL-pumped molecular laser (QPML) is a universal while revolutionary concept characterized by unprecedented frequency tunability over a wide range of rotational transitions using a single molecular gas as the gain medium. An analytical theory for QPML is presented to study the key factors for improving the laser performance. We believe that these developments will revive interest in optically pumped molecular laser as a powerful, tunable, and compact source of terahertz radiation.
Author : Andriy Danylov
Publisher :
ISBN 13 :
Total Pages : 266 pages
Book Rating : 4.:/5 (748 download)
Download or read book Frequency Stabilization, Tuning, and Spatial Mode Control of Terahertz Quantum Cascade Lasers for Coherent Transceiver Applications written by Andriy Danylov and published by . This book was released on 2010 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author : Matteo Perenzoni
Publisher : Springer
ISBN 13 : 9400738374
Total Pages : 257 pages
Book Rating : 4.4/5 (7 download)
Download or read book Physics and Applications of Terahertz Radiation written by Matteo Perenzoni and published by Springer. This book was released on 2013-10-16 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers the latest advances in the techniques employed to manage the THz radiation and its potential uses. It has been subdivided in three sections: THz Detectors, THz Sources, Systems and Applications. These three sections will allow the reader to be introduced in a logical way to the physics problems of sensing and generation of the terahertz radiation, the implementation of these devices into systems including other components and finally the exploitation of the equipment for real applications in some different field. All of the sections and chapters can be individually addressed in order to deepen the understanding of a single topic without the need to read the whole book. The THz Detectors section will address the latest developments in detection devices based on three different physical principles: photodetection, thermal power detection, rectification. The THz Sources section will describe three completely different generation methods, operating in three separate scales: quantum cascade lasers, free electron lasers and non-linear optical generation. The Systems and Applications section will take care of introducing many of the aspects needed to move from a device to an equipment perspective: control of terahertz radiation, its use in imaging or in spectroscopy, potential uses in security, and will address also safety issues. The text book is at a level appropriate to graduate level courses up to researchers in the field who require a reference book covering all aspects of terahertz technology.
Author : Nor Kamilah Binti Saat
Publisher :
ISBN 13 :
Total Pages : 308 pages
Book Rating : 4.:/5 (89 download)
Download or read book Imaging Using an Electrically Tunable Terahertz Quantum Cascade Laser written by Nor Kamilah Binti Saat and published by . This book was released on 2011 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author :
Publisher :
ISBN 13 :
Total Pages : 9 pages
Book Rating : 4.:/5 (495 download)
Download or read book Frequency Stabilization of a Single Mode Terahertz Quantum Cascade Laser to the Kilohertz Level written by and published by . This book was released on 2009 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: A simple analog locking circuit was shown to stabilize the beat signal between a 2.408 THz quantum cascade laser and a CH2DOH THz CO2 optically pumped molecular laser to 3-4 kHz (FWHM). This is approximately a tenth of the observed long-term (t ~ sec) linewidth of the optically pumped laser showing that the feedback loop corrects for much of the mechanical and acoustic-induced frequency jitter of the gas laser. The achieved stability should be sufficient to enable the use of THz quantum cascade lasers as transmitters in short-range coherent transceivers.
Author : Yu Wu
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (141 download)
Download or read book Towards Actively Mode-locked Terahertz Quantum-cascade VECSELs written by Yu Wu and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The invention of optical frequency combs generated by mode-locked lasers revolutionized time and frequency metrology in the late 1990s. This concept has been explored in several laser systems; the quantum cascade laser (QCL) is one such system that operates in the terahertz (THz) frequency range.THz QCL was first invented in 2001 as a reliable semiconductor source for compact, high-power THz radiation. The inherently strong third-order nonlinearity in its QC-gain medium allows for spontaneous frequency comb formation as a result of spatial hole burning induced by Fabry-Perot cavities and four-wave mixing, which synchronizes the dispersed cavity modes. It was noticed that the self-generated combs are naturally frequency-modulated with quasi-continuous power output, whereas amplitude-modulated combs, i.e., mode-locking, are considered challenging in THz QCLs because of the inherent fast gain recovery time. One effective method to trigger active mode-locking is RF injection locking. It involves injecting RF current modulation into the QC-device at a frequency that is close to the cavity round-trip frequency. This locks the spacing between adjacent lasing modes, and pulses with a duration of 4-5 ps have been reported. In recent years, the study of frequency comb/mode-locking in THz QCLs has raised increasing interest because of its potential for a number of applications, including astronomy, biomedicine, fast spectroscopy, non-invasive imaging, and non-destructive evaluation. So far, research has concentrated on ridge-waveguide and ring QCLs. On the other hand, THz quantum-cascade vertical-external-cavity surface-emitting-laser (QC-VECSEL) was introduced in 2015 as a novel external cavity configuration of THz QCLs.The key concept of THz QC-VECSEL is to engineer its gain chip into a millimeter-scale reflectarray metasurface for free-space THz radiation and further incorporation into a resonant laser cavity as an active reflector. This enables watt-level output power with near-Gaussian distributed beam quality; versatile functionality may be incorporated into the amplifying metasurface; and broadband frequency tunability is provided by the VECSEL architecture. Despite the fact that VECSELs are widely used for mode-locking at near-infrared and optical frequencies, THz QC-VECSELs have not yet been exploited in frequency comb and mode-locking applications. In this thesis, we report for the first time the techniques utilized to achieve frequency comb/mode-locking operations in THz QC-VECSELs. Both the metasurface design and VECSEL cavity geometry are optimized for this purpose. The double-patch metasurface design is considered optimal for broadband frequency response and low dispersion, and a well-designed RF package is needed for efficient RF signal injection and extraction. On the other hand, an off-axis parabolic (OAP) mirror is introduced to build a V-shaped intra-cryostat focusing VECSEL cavity. This OAP-focusing cavity design eliminates most of the intra-cavity diffraction losses and, therefore, enables lasing in an ultra-long external cavity using a small-sized metasurface that supports continuous wave (CW) biasing. It is highly suited for frequency comb/mode-locking applications as the cavity round-trip frequency is lowered to a typical value of 3-5 GHz. In contrast to ridge-waveguide or ring QCLs, self-generated frequency combs have not been observed in THz QC-VECSELs --- in fact, they prefer to lase in a single-mode regime primarily due to a lack of spatial hole burning.To promote multimode operation in THz QC-VECSELs, we present a technique based on a specific combination of output coupler thickness and external cavity length. Through Vernier selection and reflectance compensation in a cascaded Fabry-Perot cavity, we are able to perform simultaneous nine modes lasing with a free-spectral range (FSR) of ~21 GHz. The number of lasing modes that can be generated using this method is limited by the maximum available output coupler thickness. A more effective way to promote multimoding, as well as possible frequency comb or even mode-locking operations, is through RF injection locking.The successful demonstration of RF injection locking in THz QC-VECSELs for the first time is the main focus of this thesis. Lasing spectral broadening has been observed under strong RF modulation, with a maximum bandwidth of around 100-300 GHz. An intermodal beat-note is produced as a result of beating between each of the two lasing modes. It is locked to the RF injection signal as the injection frequency is tuned around the cavity round-trip frequency. This suggests that the lasing modes are equally spaced, which is a prerequisite of frequency comb/mode-locking. Several impacting factors, including metasurface design, external cavity length, and optical feedback, are experimentally investigated in the RF-injection locked QC-VECSELs, which may help control and tune the laser states. THz QC-VECSEL is consequently considered to be a superior platform that enables a more thorough investigation of the fundamental physics of mode-locking/frequency comb operation in QCL systems. Our research on mode-locked THz QC-VECSELs opens the way for future development of semiconductor lasers operating in the 2-5 THz region that produce picosecond-scale pulses.
Author : Thomas Folland
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (16 download)
Download or read book Frequency Control of Terahertz Quantum Cascade Lasers written by Thomas Folland and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
