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(1 - 15 of 15)
- Title
- COHERENT BEAM COMBINING OF ULTRASHORT LASER PULSES.
- Creator
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Azim, Ahmad, Shah, Lawrence, University of Central Florida
- Abstract / Description
-
Ultrashort pulsed lasers have become critical to understanding light-matter interactions in new regimes such as generation of attosecond pulses, laser filamentation, and intense relativistic processes. Development of more powerful and energetic ultrafast lasers is required for advancing these fields of study. Several petawatt class systems now exist with more in development to further scale peak power and extend the frontier of ultrafast laser technology. Another relevant solution to the...
Show moreUltrashort pulsed lasers have become critical to understanding light-matter interactions in new regimes such as generation of attosecond pulses, laser filamentation, and intense relativistic processes. Development of more powerful and energetic ultrafast lasers is required for advancing these fields of study. Several petawatt class systems now exist with more in development to further scale peak power and extend the frontier of ultrafast laser technology. Another relevant solution to the scaling of energy and power of ultrashort pulses is coherent beam combining (CBC). CBC is useful for not only scaling of laser parameters but also to mitigate parasitic nonlinear processes associated with high-intensity ultrashort pulses. In addition CBC is flexible and can be implemented as part of other techniques for ultrashort pulse amplification such as optical-parametric chirped-pulse amplification (OPCPA). In this thesis, CBC of ultrashort laser pulses is investigated based upon the method known as divided-pulse amplification (DPA). Active, passive and hybrid DPA have been achieved in a flashlamp-pumped Nd:YAG laser seeded from a Ti:sapphire mode-locked laser. Picosecond pulses at a repetition rate of 2.5 Hz were amplified and combined to record energy of 216 mJ with a combination efficiency of 80%. Engineering of the Nd:YAG amplifier chain for high-efficiency energy extraction is presented. In addition, phasing of actively divided pulses with a CW pilot laser co-propagating with the pulsed beam is also demonstrated. Analysis of multiple DPA configurations shows the viability of the method for a variety of different laser architectures including discussion of design restrictions.
Show less - Date Issued
- 2016
- Identifier
- CFH2000034, ucf:45599
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH2000034
- Title
- System for metal coated fiber fabrication.
- Creator
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Zhang, Da, Amezcua Correa, Rodrigo, Schulzgen, Axel, Shah, Lawrence, University of Central Florida
- Abstract / Description
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For many specific applications, such as sensors, aerospace, chemical industry, deep-well oil-field industry, metal-coated fiber shows strong abilities to satisfy people's requirement. With in-line coating technology, we are able to coat Aluminum on the fibers.Using electromagnetic induction, we can easily heat an electrically conducting thing such as a metal with the eddy current. This process is defined as Induction heating. And we will melt the Aluminum by this induction heating during...
Show moreFor many specific applications, such as sensors, aerospace, chemical industry, deep-well oil-field industry, metal-coated fiber shows strong abilities to satisfy people's requirement. With in-line coating technology, we are able to coat Aluminum on the fibers.Using electromagnetic induction, we can easily heat an electrically conducting thing such as a metal with the eddy current. This process is defined as Induction heating. And we will melt the Aluminum by this induction heating during drawing the fibers on the tower. Introduce the fiber tower system. The drawing process of in-line technology is formed of the following steps: Position, Melting, Forming into fibers, Checking the diameter, Revising, Protective coatings. We will follow these to make the Aluminum coating fiber.With the help of the software which is 123D Design, I have four 3D model of the coating systems. Show the details of the all the coating systems such as the shape and the length of coated-fiber we can get.Talk about the photonic lantern which is the first project that I took part in when I joined the group. Show the mode profiles of our 6 to 1 lantern.
Show less - Date Issued
- 2017
- Identifier
- CFE0006677, ucf:51251
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006677
- Title
- Design and Verification of a Multi-Terawatt Ti-Sapphire Femtosecond Laser System.
- Creator
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Roumayah, Patrick, Shah, Lawrence, Richardson, Martin, Amezcua Correa, Rodrigo, University of Central Florida
- Abstract / Description
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Ultrashort pulse lasers are well-established in the scientific community due to the wide range of applications facilitated by their extreme intensities and broad bandwidth capabilities. This thesis will primarily present the design for the Mobile Ultrafast High Energy Laser Facility (MU-HELF) for use in outdoor atmospheric propagation experiments under development at the Laser Plasma Laboratory at UCF. The system is a 100fs 500 mJ Ti-Sapphire Chirped-Pulse Amplification (CPA) laser, operating...
Show moreUltrashort pulse lasers are well-established in the scientific community due to the wide range of applications facilitated by their extreme intensities and broad bandwidth capabilities. This thesis will primarily present the design for the Mobile Ultrafast High Energy Laser Facility (MU-HELF) for use in outdoor atmospheric propagation experiments under development at the Laser Plasma Laboratory at UCF. The system is a 100fs 500 mJ Ti-Sapphire Chirped-Pulse Amplification (CPA) laser, operating at 10 Hz. Some background on the generation of very high intensity optical pulses is also presented, alongside an overview of the physics of filamentation. As part of the design of MU-HELF, this thesis focuses on a novel approach to manage the large amount of dispersion required to stretch the pulse for CPA utilizing a custom nonlinear chirped Volume Bragg Grating (VBG) as a pulse stretcher matched to a traditional Treacy compressor. As part of this thesis, the dispersion of the CPA system was thoroughly modeled to properly design the chirped VBG and fabricated VBGs were characterized using a scanning spectral interferometry technique. The work demonstrates the feasibility of using a compact monolithic pulse stretcher in terawatt class CPA lasers.
Show less - Date Issued
- 2017
- Identifier
- CFE0006651, ucf:51241
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006651
- Title
- Filament Wavefront Evolution.
- Creator
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Thul, Daniel, Richardson, Martin, Shah, Lawrence, Baudelet, Matthieu, University of Central Florida
- Abstract / Description
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Filamentation is a complex process that gives rise to many nonlinear interactions. However, the fundamentals of filament formation and propagation can be explained in terms of two dominant mechanisms: Kerr self-focusing and plasma defocusing. The first to occur, self-focusing, is responsible for an increase in irradiance through beam collapse. This process requires sufficient initial peak power, on the order of gigawatts for near infrared beams in air. Plasma defocusing then arrests the...
Show moreFilamentation is a complex process that gives rise to many nonlinear interactions. However, the fundamentals of filament formation and propagation can be explained in terms of two dominant mechanisms: Kerr self-focusing and plasma defocusing. The first to occur, self-focusing, is responsible for an increase in irradiance through beam collapse. This process requires sufficient initial peak power, on the order of gigawatts for near infrared beams in air. Plasma defocusing then arrests the collapse process once the irradiance reaches the ionization threshold of the medium. These two pro-cesses balance each other in an extended plasma channel known as a filament. A beam's collapse behavior is strongly influenced by the initial beam conditions, espe-cially in applications that require power scaling to terawatt levels where the Kerr effect is more pronounced. Therefore, understanding and controlling the collapse process is essential in this regime. For this reason, an exploration of the wavefront evolution of filamenting beams is of great interest and the topic of this thesis, which has three parts. First, it reviews the filamentation process and describes characteristics of filaments. Next, experimental measurements of the wavefronts of filamenting beams are given in two separate regimes. The first regime is the Kerr self-focusing that takes place before beam collapse is arrested. This data is then contrasted with wavefront measurements within a filament after collapse has occurred.
Show less - Date Issued
- 2017
- Identifier
- CFE0006808, ucf:51804
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006808
- Title
- Laser-induced crystallization mechanisms in chalcogenide glass materials for advanced optical functionality.
- Creator
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Sisken, Laura, Richardson, Kathleen, Richardson, Martin, Shah, Lawrence, University of Central Florida
- Abstract / Description
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Glass-ceramics (GC) are promising candidates for gradient refractive index (GRIN) optics. These multi-phase, composite materials also exhibit improved physical properties as compared to the parent base glass resulting from the formation of a secondary crystalline phase(s). Nanocrystal phase formation in a multi-component chalcogenide glass (ChG), (GeSe2-3As2Se3)(1-x)-(PbSe)x glass where x = 0-40 has been investigated, and the role of the starting material morphology has been correlated to the...
Show moreGlass-ceramics (GC) are promising candidates for gradient refractive index (GRIN) optics. These multi-phase, composite materials also exhibit improved physical properties as compared to the parent base glass resulting from the formation of a secondary crystalline phase(s). Nanocrystal phase formation in a multi-component chalcogenide glass (ChG), (GeSe2-3As2Se3)(1-x)-(PbSe)x glass where x = 0-40 has been investigated, and the role of the starting material morphology has been correlated to the resulting composite's optical properties including refractive index, transmission, dispersion, and thermo-optic coefficient. Optical property evolution was related to the type and amount of the crystal phases formed, since through control of the local volume fraction of crystalline phase(s), the effective material properties of the composite can locally be varied. Through computational and experimental studies, tailored nanocomposites exhibiting gradient index properties have been realized. A Raman spectroscopic technique was developed as a means to spatially quantify the extent of conversion from glass to glass ceramic, and to confirm that the scale length of the local refractive index modification can be correlated to the extent of crystallization as validated by X-ray diffraction (XRD). Spatial control of the crystallization was examined by using a laser to locally modify the amount of nucleation and/or growth of crystallites in the glass. A novel technique converse to laser-induced crystallization was also developed and demonstrated that a glass ceramic could be locally re-vitrified back to a fully glassy state, through a laser-induced vitrification (LIV) method. Proof-of-concept demonstrator optics were developed using furnace and laser induced crystallization methods to validate experimental and computational approaches to modify the local volume fraction of nano-crystals. These demonstrators exhibited tailorable optical functionality as focusing optics and diffractive optics. This work paves the way for the design and fabrication of nanocomposite GRIN optics and their use in the mid-wave infrared.
Show less - Date Issued
- 2017
- Identifier
- CFE0006916, ucf:51684
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006916
- Title
- High Average Power Nanosecond Pulsed Tm:Fiber Laser for Pumping an Optical Parametric Oscillator.
- Creator
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Abdulfattah, Ali, Richardson, Martin, Shah, Lawrence, Delfyett, Peter, University of Central Florida
- Abstract / Description
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Thulium-doped fiber lasers operating with wavelengths in the vicinity of 2 (&)#181;m are useful for several emerging applications including generating mid-IR light via nonlinear frequency conversion. In this study we describe the design and construction of a thulium fiber laser system comprising a master oscillator and a power amplifier. The first stage is a Q-switched, thulium-doped photonic crystal fiber oscillator utilizing an acousto-optic modulator to produce 65-80 nanosecond pulses. A...
Show moreThulium-doped fiber lasers operating with wavelengths in the vicinity of 2 (&)#181;m are useful for several emerging applications including generating mid-IR light via nonlinear frequency conversion. In this study we describe the design and construction of a thulium fiber laser system comprising a master oscillator and a power amplifier. The first stage is a Q-switched, thulium-doped photonic crystal fiber oscillator utilizing an acousto-optic modulator to produce 65-80 nanosecond pulses. A diffraction grating in the cavity provides wavelength tunability from 1.8 (-) 2?m. The oscillator produced up to 3 W of average power and 150 (&)#181;J pulse energies, corresponding to 2.3 kW peak powers. The amplifier stage consists of a large mode area, thulium-doped, step-index fiber seeded with powers up to 2 W from the oscillator. An output energy of 700 (&)#181;J with 81 ns pulse width, was achieved at a wavelength of 1.9 (&)#181;m. The effect of the fiber holder temperature on the amplifier performance relative to output pulse energy and seed wavelength was also studied. As a part of this thesis, a methodology has been developed to thoroughly characterize Tm:fiber amplifier performance. This has been the subject of prior work by several research groups, however, this work explicitly focuses on the precise characterization of absorbed pump power, pump bleaching, and extracted amplified energy for a range of input seeds power, pulse energy, and wavelength in order to better understand amplifier performance.
Show less - Date Issued
- 2016
- Identifier
- CFE0006240, ucf:51065
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006240
- Title
- Photothermal Lensing in Mid-Infrared Materials.
- Creator
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Cook, Justin, Richardson, Martin, Shah, Lawrence, Gaume, Romain, University of Central Florida
- Abstract / Description
-
A thorough understanding of laser-materials interactions is crucial when designing and building optical systems. An ideal test method would probe both the thermal and optical properties simultaneously for materials under large optical loads where detrimental thermal effects emerge. An interesting class of materials are those used for infrared wavelengths due to their wide spectral transmission windows and large optical nonlinearities. Since coherent sources spanning the mid-wave and long-wave...
Show moreA thorough understanding of laser-materials interactions is crucial when designing and building optical systems. An ideal test method would probe both the thermal and optical properties simultaneously for materials under large optical loads where detrimental thermal effects emerge. An interesting class of materials are those used for infrared wavelengths due to their wide spectral transmission windows and large optical nonlinearities. Since coherent sources spanning the mid-wave and long-wave infrared wavelength regions have only become widely available in the past decade, data regarding their thermal and optical responses is lacking in literature.Photothermal Lensing (PTL) technique is an attractive method for characterizing the optical and thermal properties of mid-infrared materials as it is nondestructive and can be implemented using both continuous wave and pulsed irradiation. Analogous to the well-known Z-scan, the PTL technique involves creating a thermal lens within a material and subsequently measuring this distortion with a probe beam. By translating the sample through the focus of the pump laser, information can be obtained regarding the nonlinear absorption, thermal diffusivity and thermo-optic coefficient. This thesis evaluates the effectiveness and scope of the PTL method using numerical simulations of low loss infrared materials. Specifically, the response of silicon, germanium, and As2Se3 glass is explored. The 2 ?m pump and 4.55 ?m probe beam geometries are optimized in order to minimize experimental error. Methodologies for estimating the thermal diffusivity, nonlinear absorption coefficient and thermo-optic coefficient directly from the experimentally measured PTL signal are presented. Finally, the ability to measure the nonlinear absorption coefficient without the need for high-energy or ultrashort optical pulses is demonstrated.
Show less - Date Issued
- 2017
- Identifier
- CFE0006730, ucf:51885
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006730
- Title
- Design of a hydrogen-filled hollow-core Raman fiber laser.
- Creator
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Qin, Yangyang, Amezcua Correa, Rodrigo, Schulzgen, Axel, Shah, Lawrence, University of Central Florida
- Abstract / Description
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The purpose of this study is to investigate the design of a Raman fiber laser based on a molecule hydrogen-filled hollow-core fiber with non-touching single ring of capillaries structure. O-hydrogen vibrational frequency shift of 4155 cm-1 and rotational frequency shift of 587 cm-1 were employed to generate Raman scattering from a 1064nm pump source.A thorough exploration was made to show how all Raman fiber laser components made up: gas chamber, hollow-core fibers, windows. The whole process...
Show moreThe purpose of this study is to investigate the design of a Raman fiber laser based on a molecule hydrogen-filled hollow-core fiber with non-touching single ring of capillaries structure. O-hydrogen vibrational frequency shift of 4155 cm-1 and rotational frequency shift of 587 cm-1 were employed to generate Raman scattering from a 1064nm pump source.A thorough exploration was made to show how all Raman fiber laser components made up: gas chamber, hollow-core fibers, windows. The whole process of chamber design, modification and fabrication were demonstrated. Besides, two kinds of anti-resonant hollow-core fibers were studied and tested. The transmission and loss spectrum of these fibers were measured thus it's easier to make a choice. Through the whole thesis a Raman fiber laser can be set up and tested very soon.
Show less - Date Issued
- 2017
- Identifier
- CFE0006645, ucf:51213
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006645
- Title
- Peak Power Scaling of Nanosecond Pulses in Thulium based Fiber Lasers.
- Creator
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Gaida, Christian, Richardson, Martin, Shah, Lawrence, Amezcua Correa, Rodrigo, University of Central Florida
- Abstract / Description
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Thulium based fiber lasers represent a promising alternative for pulse energy scaling and highpeak power generation with ytterbium based systems at 1 micrometer. Advantages of thulium arise fromthe operation at longer wavelengths and a large gain bandwidth (1.8-2.1 micrometer). Nonlinear effects,such as self phase modulation, stimulated Raman scattering and stimulated Brillouin scattering generally limit peak power scaling in fiber lasers. The longer wavelength of thulium fiber lasersand...
Show moreThulium based fiber lasers represent a promising alternative for pulse energy scaling and highpeak power generation with ytterbium based systems at 1 micrometer. Advantages of thulium arise fromthe operation at longer wavelengths and a large gain bandwidth (1.8-2.1 micrometer). Nonlinear effects,such as self phase modulation, stimulated Raman scattering and stimulated Brillouin scattering generally limit peak power scaling in fiber lasers. The longer wavelength of thulium fiber lasersand large mode field areas can significantly increase the nonlinear thresholds. Compared to 1 micrometer systems, thulium fiber lasers enable single mode guidance for two times larger mode field diameterin step index fibers. Similar behavior is expected for index guiding thulium doped photonic crystalfibers.In this work a novel thulium doped rod type photonic crystal fiber design with large mode field diameter (>50 micrometer) was first characterized in CW-lasing configuration and then utilized as finalamplifier in a two stage master oscillator power amplifier. The system generated MW-level peakpower at 6.5ns pulse duration and 1kHz repetition rate. This world record performance exemplifiesthe potential of thulium fiber lasers to supersede ytterbium based systems for very high peak powergeneration in the future.As part of this work a computer model for the transient simulation of pulsed amplification inthulium based fiber lasers was developed. The simulations are in good agreement with the experimentalresults. The computer model can be used for efficient optimization of future thulium basedfiber amplifier designs.
Show less - Date Issued
- 2013
- Identifier
- CFE0004845, ucf:49699
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004845
- Title
- Broad Bandwidth, All-fiber, Thulium-doped Photonic Crystal Fiber Amplifier for Potential Use in Scaling Ultrashort Pulse Peak Powers.
- Creator
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Sincore, Alex, Richardson, Martin, Shah, Lawrence, Amezcua Correa, Rodrigo, University of Central Florida
- Abstract / Description
-
Fiber based ultrashort pulse laser sources are desirable for many applications; however generating high peak powers in fiber lasers is primarily limited by the onset of nonlinear effects such as self-phase modulation, stimulated Raman scattering, and self-focusing. Increasing the fiber core diameter mitigates the onset of these nonlinear effects, but also allows unwanted higher-order transverse spatial modes to propagate. Both large core diameters and single-mode propagation can be...
Show moreFiber based ultrashort pulse laser sources are desirable for many applications; however generating high peak powers in fiber lasers is primarily limited by the onset of nonlinear effects such as self-phase modulation, stimulated Raman scattering, and self-focusing. Increasing the fiber core diameter mitigates the onset of these nonlinear effects, but also allows unwanted higher-order transverse spatial modes to propagate. Both large core diameters and single-mode propagation can be simultaneously attained using photonic crystal fibers.Thulium-doped fiber lasers are attractive for high peak power ultrashort pulse systems. They offer a broad gain bandwidth, capable of amplifying sub-100 femtosecond pulses. The longer center wavelength at 2 ?m theoretically enables higher peak powers relative to 1 ?m systems since nonlinear effects inversely scale with wavelength. Also, the 2 ?m emission is desirable to support applications reaching further into the mid-IR.This work evaluates the performance of a novel all-fiber pump combiner that incorporates a thulium-doped photonic crystal fiber. This fully integrated amplifier is characterized and possesses a large gain bandwidth, essentially single-mode propagation, and high degree of polarization. This innovative all-fiber, thulium-doped photonic crystal fiber amplifier has great potential for enabling high peak powers in 2 ?m fiber systems; however the current optical-to-optical efficiency is low relative to similar free-space amplifiers. Further development and device optimization will lead to higher efficiencies and improved performance.
Show less - Date Issued
- 2014
- Identifier
- CFE0005260, ucf:50611
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005260
- Title
- Distribution of Laser Induced Heating in Multi-Component Chalcogenide Glass and its Associated Effects.
- Creator
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Sisken, Laura, Richardson, Kathleen, Richardson, Martin, Shah, Lawrence, University of Central Florida
- Abstract / Description
-
Chalcogenide glasses are well known to have good transparency into the infrared spectrum. These glasses though tend to have low thresholds as compared to oxide glasses for photo-induced changes and thermally-induced changes. Material modification such as photo-induced darkening, bleaching, refractive index change, densification or expansion, ablation of crystallization have been demonstrated, and are typically induced by a thermal furnace-based heat treatment, an optical source such as a...
Show moreChalcogenide glasses are well known to have good transparency into the infrared spectrum. These glasses though tend to have low thresholds as compared to oxide glasses for photo-induced changes and thermally-induced changes. Material modification such as photo-induced darkening, bleaching, refractive index change, densification or expansion, ablation of crystallization have been demonstrated, and are typically induced by a thermal furnace-based heat treatment, an optical source such as a laser, or a combination of photo-thermal interactions. Solely employing laser-based heating has an advantage over a furnace, since one has the potential to be able to spatially modify the materials properties with much greater precision by moving either the beam or the sample.The main properties of ChG glasses investigated in this study were the light-induced and thermally-induced modification of the glass through visible microscopy, white light interferometry, and Raman spectroscopy. Additionally computational models were developed in order to aid in determining what temperature rise should be occurring under the conditions used in experiments.It was seen that ablation, photo-expansion, crystallization, and melting could occur for some of the irradiation conditions that were used. The above bandgap energy simulations appeared to overestimate the maximum temperature that should have been reached in the sample, while the below bandgap energy simulations appeared to underestimate the maximum temperature that should have been reached in the sample. Ultimately, this work produces the ground work to be able to predict and control dose, and therefore heating, to induce localized crystallization and phase change.
Show less - Date Issued
- 2014
- Identifier
- CFE0005261, ucf:50606
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005261
- Title
- 2 micron fiber lasers: power scaling concepts and limitations.
- Creator
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Sincore, Alex, Richardson, Martin, Amezcua Correa, Rodrigo, Schulzgen, Axel, Shah, Lawrence, University of Central Florida
- Abstract / Description
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Thulium- and holmium-doped fiber lasers (TDF and HDF) emitting at 2 micron offer unique benefits and applications compared to common ytterbium-doped 1 micron lasers. This dissertation details the concepts, limitations, design, and performance of four 2 micron fiber laser systems. While these lasers were developed for various end-uses, they also provide further insight into two major power scaling limitations. The first limitation is optical nonlinearities: specifically stimulated Brillouin...
Show moreThulium- and holmium-doped fiber lasers (TDF and HDF) emitting at 2 micron offer unique benefits and applications compared to common ytterbium-doped 1 micron lasers. This dissertation details the concepts, limitations, design, and performance of four 2 micron fiber laser systems. While these lasers were developed for various end-uses, they also provide further insight into two major power scaling limitations. The first limitation is optical nonlinearities: specifically stimulated Brillouin scattering (SBS) and modulation instability (MI). The second limitation is thermal failure due to inefficient pump conversion. First, a 21.5 W single-frequency, single-mode laser with adjustable output from continuous-wave to nanosecond pulses is developed. Measuring the SBS threshold versus pulse duration enables the Brillouin gain coefficient and gain bandwidth to be determined at 2 micron. Second, a 23 W spectrally-broadband, nanosecond pulsed laser is constructed for materials processing applications. The temporally incoherent multi-kW peak power pulses can also efficiently produce MI and supercontinuum generation by adjusting the input spectral linewidth. Third, the measured performance of in-band pumped TDF and HDF lasers are compared with simulations. HDF displays low efficiencies, which is explained by including ion clustering in the simulations. The TDF operates with impressive (>)90% slope efficiencies. Based on this result, a system design for (>)1 kW average power TDF amplifier is described. The designed final amplifier will be in-band pumped to enable high efficiency and low thermal load. The amplifier efficiency, operating bandwidth, thermal load, and nonlinear limits are modeled and analyzed to provide a framework for execution. Overall, this dissertation provides further insight and understanding on the various processes that limit power scaling of 2 micron fiber lasers.
Show less - Date Issued
- 2018
- Identifier
- CFE0007374, ucf:52105
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007374
- Title
- Design and Engineering Criteria for Optical Parametric Chirped Pulse Amplifier Systems.
- Creator
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Bodnar, Nathan, Richardson, Martin, Delfyett, Peter, Likamwa, Patrick, Baudelet, Matthieu, Shah, Lawrence, University of Central Florida
- Abstract / Description
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The generation of a quasi-single-cycle laser light pulse is a goal in many laser applications experiments. Some involve in High Harmonic Generation (HHG) and Attosecond Sciences. The demand for ultrafast laser facilities has grown; the techniques and availability of materials have changed; thereby posing new design challenges in building Optical Parametric Chirped Pulse Amplification (OPCPA) laser facilities. The concepts and challenges are discussed in detail in the development of two laser...
Show moreThe generation of a quasi-single-cycle laser light pulse is a goal in many laser applications experiments. Some involve in High Harmonic Generation (HHG) and Attosecond Sciences. The demand for ultrafast laser facilities has grown; the techniques and availability of materials have changed; thereby posing new design challenges in building Optical Parametric Chirped Pulse Amplification (OPCPA) laser facilities. The concepts and challenges are discussed in detail in the development of two laser systems within the Laser Plasma Laboratory, HERACLES and PhaSTHEUS. This dissertation also gives insight to the challenges that are encountered in other cutting edge OPCPA laser facilities. An overview of the design challenges that need to be addressed in any OPCPA laser facility either high energy or high average power that is suitable for high intensity laser physics is discussed in this dissertation.
Show less - Date Issued
- 2018
- Identifier
- CFE0007158, ucf:52300
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007158
- Title
- Design and Engineering of Ultrafast Amplifier Systems.
- Creator
-
Webb, Benjamin, Richardson, Martin, Chang, Zenghu, Delfyett, Peter, Gaume, Romain, Shah, Lawrence, Klemm, Richard, University of Central Florida
- Abstract / Description
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Recently, the design and engineering of ultrafast laser systems have led to an extraordinary increase in laser power and performance which have brought about advances in many fields such as medicine, material processing, communications, remote sensing, spectroscopy, nonlinear optics, and atomic physics. In this work, several ultrafast amplification techniques -- including chirped-pulse amplification (CPA), optical parametric chirped-pulse amplification (OPCPA), and divided-pulse amplification...
Show moreRecently, the design and engineering of ultrafast laser systems have led to an extraordinary increase in laser power and performance which have brought about advances in many fields such as medicine, material processing, communications, remote sensing, spectroscopy, nonlinear optics, and atomic physics. In this work, several ultrafast amplification techniques -- including chirped-pulse amplification (CPA), optical parametric chirped-pulse amplification (OPCPA), and divided-pulse amplification (DPA) -- are described and demonstrated in the design and construction of two ultrafast laser facilities. An existing Ti:Sapphire laser system was completely redesigned with an increased power of 10 TW for experiments capable of generating hundreds of laser filaments in ordered arrays. The performance of DPA above the Joule-level was investigated in a series of experiments utilizing various DPA schemes with gain-saturated amplifiers at high pulse energy. A new high energy OPCPA facility has been designed and its pump laser system constructed, utilizing the technique of DPA for the first time in a flashlamp-pumped amplifier chain and with a record combined energy of 5 Joules in a 230 ps pulse duration. The demonstrated OPCPA pump performance will allow for the generation of 50 TW quasi-single cycle 5 fs pulses at 2.5 Hz from a table-top OPCPA system.
Show less - Date Issued
- 2016
- Identifier
- CFE0006547, ucf:51349
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006547
- Title
- Fiber Optimization for Operation Beyond Transverse Mode Instability Limitations.
- Creator
-
Bradford, Joshua, Richardson, Martin, Gaume, Romain, Amezcua Correa, Rodrigo, Shah, Lawrence, University of Central Florida
- Abstract / Description
-
Transverse Mode Instabilities (TMIs) stand as a fundamental limitation to power and brightness scaling in laser systems based upon optical fiber technologies. This work comprises experimental and theoretical investigations into fiber laser design that should minimize the effects of Stimulated Thermal Rayleigh Scattering. Theoretical discussions and simulations focus on how fiber parameters affect transverse mode coupling. These include core geometry optimization, pump geometry optimization,...
Show moreTransverse Mode Instabilities (TMIs) stand as a fundamental limitation to power and brightness scaling in laser systems based upon optical fiber technologies. This work comprises experimental and theoretical investigations into fiber laser design that should minimize the effects of Stimulated Thermal Rayleigh Scattering. Theoretical discussions and simulations focus on how fiber parameters affect transverse mode coupling. These include core geometry optimization, pump geometry optimization, in addition to the effects of HOM content and losses on the TMI threshold. Experimentally, a high-power laser facility is commissioned with beam quality diagnostics to quantify the thresholds of the onset of modal interferences and their impacts on beam quality. These diagnostics include high-resolution Fourier Transform Interferometry (FTI) and in-situ power-in-the-bucket measurements. The design and characterization capabilities developed here are crucial to the development of next-generation high-power fiber laser capabilities.
Show less - Date Issued
- 2018
- Identifier
- CFE0006980, ucf:51646
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006980
