Download or read book Diode pumped Continuous wave and Femtosecond Cr LiCAF Lasers with High Average Power in the Near Infrared Visible and Near Ultraviolet written by Umit Demirbas and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low cost Highly Efficient and Tunable Ultrafast Laser Technology Based on Directly Diode pumped Cr Colquiriites written by Umit Demirbas and published by . This book was released on 2010 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: This doctoral project aims to develop robust, ultra low-cost ($5,000-20,000), highly-efficient, and tunable femtosecond laser technology based on diode-pumped Cr:Colquiriite gain media (Cr:LiCAF, Cr3+:LiSAF and Cr:LiSGaF). By using inexpensive single-mode diodes ($150) as the pump source, we have obtained continuous-wave (cw) output powers>250-mW with slope efficiencies>50%. Record cw tuning ranges were demonstrated for Cr:LiSAF (775-1042 nm), Cr:LiSGaF (777-977 nm), and Cr:LiCAF (754-871 nm). For femtosecond pulse generation, semiconductor saturable absorber mirrors (SESAMs/SBRs) were developed, which were used to initiate and sustain mode-locking. Typical performance was ~25-100 fs pulses, with an optical spectrum in the 770-920 nm range, with ~1-2 nJ of pulse energies from ~100-MHz repetition rate cavities. Record electrical-to-optical conversion efficiencies of ~10% were demonstrated in the cw mode-locked regime. A mode-locked tuning range of 767-817 nm, with ~130-fs long pulses was obtained by using Cr:LiCAF as gain medium. With the Cr:LiSAF gain medium, using regular SESAMs/SBRs centered around 800 nm, 850 nm, and 910 nm, mode-locked tuning ranges of 803-831 nm, 828-873 nm, and 890-923 nm were demonstrated, respectively. By using a broadband oxidized SESAM/SBR, a record tuning range of 800-905 nm was demonstrated with ~150-fs long pulses. Using an extended cavity Cr:LiCAF laser, pulse energies>15-nJ with peak powers exceeding 100-kW were obtained. We performed the first cavity-dumping experiments with a Cr:Colquiriite laser and demonstrated pulse energies>100-nJ, and peak powers approaching MW level, at repetition rates up to 50-kHz. Cr:LiCAF gain media were also pumped by single-emitter multimode diodes, where we obtained>2-W output power in cw operation, and ~100-fs pulses with 390-mW of average power at a repetition rate of 140 MHz in cw mode-locked operation. As an example application area for this low cost technology, we performed multiphoton microcopy experiments with a single-mode diode-pumped Cr:LiCAF laser. We also performed attosecond-resolution timing jitter characterization experiments of the femtosecond Cr:LiSAF laser, and measured a record-low upper limit for the integrated timing jitter of the Cr:LiSAF laser (137-attoseconds in 10 kHz-10 MHz range).
Download or read book Optics Letters written by and published by . This book was released on 2007 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 1460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1994 with total page 898 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Average Power Diode Pumped Solid State Lasers Power Scaling With High Spectral and Spatial Coherence written by and published by . This book was released on 2009 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main program objective was the development of a kilowatt class, cw Nd:YAG diode-laser-pumped solid-state laser (DPSSL) with quantum noise limited amplitude and phase, 24by7 operation capability and the ability to be repaired while in operation. The approach was a master-oscillator power-amplifier (MOPA) laser utilizing a series of zig-zag slab power amplifiers stages. We developed fiber amplifiers at the 200W level to generate power with high optical efficiency that can effectively extract energy from the power amplifier slabs. We also worked on the generation of high average power visible light by developing nonlinear optical materials with large apertures, low photo-refraction and minimal visible induced infrared absorption. The second objective was to develop a 1 joule, pulse-modulated, diffraction limited MOPA laser with less than 1 MHz line-width. A follow-on objective was frequency conversion to 1.5 or 2.0 microns for remote sensing applications. We demonstrated Yb:YAG slab lasers pumped with high brightness laser diodes. Supporting this project was the development of laser diodes operating in the 1.5 micron region for pumping of erbium doped laser hosts, and the synthesis of new low-loss polycrystalline laser host materials for in-band pumping into the upper laser level to improve the laser efficiency at eye-safe wavelengths. We developed orientation patterned Ga-As to frequency convert high peak power 1-micron radiation to eye-safe wavelengths in the mid-infrared for defense applications. The third objective, power scaling and determining the potential for phase-locking of ultra-fast laser systems for a wide range of sensing and machining applications, was demonstrated as well.
Download or read book Continuous wave Diode pumped Cr YAG Laser written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Femtosecond Cr LiSAF and Cr LiCAF Lasers Pumped by Tapered Diode Lasers written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Efficient CW Nd YLF Laser In band Diode pumped at 908 Nm and Its Thermal Lensing written by Zohreh Sedaghati and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diode-pumped solid-state lasers are highly recommended for a variety of industrial and scientific applications as they can offer high efficiency and excellent beam quality. However, power scaling of these lasers is a challenging task. The main limitation in power scaling of famous neodymium doped lasers such as Nd:YVO4 is the thermal lensing effect. Thermal lensing degrades the output beam quality and in extreme cases can result in crystal fracture. One potential solution to this problem is to reduce the induced heat load inside the gain media by decreasing the quantum defect. This was demonstrated successfully for the Nd:YVO4 laser by pumping the laser at a long wavelength of 914 nm instead of the traditional pumping at 808 nm wavelength. Among the Nd-doped crystals operating in the near infrared range, the crystal of yttrium lithium fluoride (Nd:YLF) is another interesting gain medium as it has the benefits of natural birefringence (can generate naturally polarized laser beam), negative dn/dT (reduces thermal effects) and long upper level lifetime (in favor of Q-switched operation). In this work we used a long wavelength pumping approach and for the first time examined the performance of a continuous-wave Nd:YLF laser at 1047 nm under 908 nm diode pumping. This pumping wavelength reduced the quantum defect by 50% as compared to the conventional 808 nm pumping. The laser produced an output power of 850 mW at 1047 nm with excellent beam quality and 625 mW at 1053 nm. The slope efficiency was ~73.9% and 46% for 1047 and 1053 nm, respectively. Therefore, a considerable power scaling is possible for Nd:YLF crystals owing to the strongly reduced quantum defect and, hence, thermal lensing.
Download or read book Development of Sub 50 fs Laser Oscillator with Mega watt Peak Power for Nonlinear Applications written by Sujith Manjooran and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: For several biomedical nonlinear applications mega-watt (MW) peak power lasers working in the near-infrared (NIR) wavelength range are desirable. A cost-effective diode-pumped sub-100-fs solid-state laser oscillator with MW peak power in the NIR wavelength range is not readily available on the commercial market. This thesis presents the successful development of several high power continuous wave (CW) and intense short pulse laser designs. Two laser gain media, namely Yb:KY(WO4)2 (Yb:KYW) and Yb: CaGdAlO4 (Yb:CALGO), were studied in this thesis. These solid-state laser crystals were end-pumped with high power diode laser at ~980 nm. Initially, the continuous wave operation of Yb:KYW with 9W of output power at 1045 nm was demonstrated. The developed Yb:KYW had the highest slope efficiency of 77.9% when compared to all other diode-pumped Yb:KYW lasers. At the same time the developed Yb:CALGO laser was capable of delivering tunable multi-watt output power in the wavelength range of approximately 1020 nm to 1070 nm. Based on these results two intense short pulse lasers were designed and developed in this thesis. The first one was a sub-50-fs Kerr-lens and saturable absorber (KLAS) mode-locked Yb:CALGO laser oscillator with a repetition rate of 42.3 MHz. The highest peak power achieved for 45-fs pulses directly from the oscillator was 1.7 MW. The shortest generated pulses were 38-fs with 187 kW of peak power. The second laser was a sub-100-fs Kerr-lens mode-locked (KLM) Yb:CALGO laser with a low repetition rate of 10.2 MHz. The oscillator produced 650 mW of average output power with pulse duration of 66 fs. It also generated 1 W of average power with pulse duration of 72 fs. This corresponds to pulse energy of 64 nJ with a peak power of 0.97 MW and 98 nJ with the peak power of 1.36 MW, respectively. Some of the nonlinear applications of the high intense laser pulses were studied in the final section. Phase-matching conditions of three periodically poled crystals (PPKTP, MgO:PPcLN and MgO:PPSLT) for use in femtosecond optical parametric oscillators (OPO) to generate wavelength tunability in the NIR range were studied. The developed intense short pulse lasers in this project have numerous applications not only in biomedical research but also in fundamental science and industry.
Download or read book Diode Pumped Solid State DPSS Lasers written by Mark W. Dowley and published by . This book was released on 1998 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High average power Diode pumped Yb written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A scaleable diode end-pumping technology for high-average-power slab and rod lasers has been under development for the past several years at Lawrence Livermore National Laboratory (LLNL). This technology has particular application to high average power Yb:YAG lasers that utilize a rod configured gain element. Previously, this rod configured approach has achieved average output powers in a single 5 cm long by 2 mm diameter Yb:YAG rod of 430 W cw and 280 W q-switched. High beam quality (M2 = 2.4) q-switched operation has also been demonstrated at over 180 W of average output power. More recently, using a dual rod configuration consisting of two, 5 cm long by 2 mm diameter laser rods with birefringence compensation, we have achieved 1080 W of cw output with an M2 value of 13.5 at an optical-to-optical conversion efficiency of 27.5%. With the same dual rod laser operated in a q-switched mode, we have also demonstrated 532 W of average power with an M2
Download or read book High Power Operation of the In band Diode pumped Nd GdVO4 Lasers written by Mohammad Nadimi and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main obstacle in power scaling of the well-known Nd-doped lasers such as Nd:YVO4 is the thermal lensing effect. One of the proposed solutions to effectively alleviate this problem was based on the reduction of heating within the laser crystal. This was extensively investigated with the Nd:YVO4 crystal by pumping the laser at 914 nm instead of the standard pumping at 808 nm wavelength. In context of high power applications, the crystal of Nd:GdVO4 is an interesting alternative to the Nd:YVO4 as it offers the benefits of good spectral features (similar to Nd:YVO4) and much higher thermal conductivity. However, there is only one proof-of-principle work on continuous-wave (CW) Nd:GdVO4 laser using this pumping approach in which an output power of 3.35 W was reported. The full power scaling potential of the Nd:GdVO4 laser crystal to produce high output power has not been demonstrated to date. In this PhD thesis, I addressed this issue and investigated the high power operation of Nd:GdVO4 lasers under a new pumping wavelength of 912 nm. First, the thermal lensing behaviour of a 1063 nm Nd:GdVO4 was studied, both experimentally and by finite element analysis (FEA) method. The thermal lensing strength in Nd:GdVO4 laser under 912 nm pumping was significantly reduced when compared to the Nd:GdVO4 laser with 808 nm pumping or even Nd:YVO4 laser with 914 nm pumping. The next step of this research was focused on high power operation of Nd:GdVO4 lasers where we achieved 19.8 W of output power at 1063 nm. As a side work in the CW regime of operation, the possibility of discrete wavelength tuning and dual-wavelength operation of the Nd:GdVO4 laser were examined by using an intracavity birefringent filter. Discrete wavelength operation at four different wavelengths was demonstrated. Furthermore, for the first time we were able to demonstrate a dual-wavelength operation of the Nd:GdVO4 laser as a 1063 and 1071 nm wavelength pair. The last aspect of this PhD thesis was concentrated on generation of picosecond pulses. We were able to report on the first semiconductor saturable absorber mirror (SESAM) mode-locked (ML) Nd:GdVO4 laser with 912 nm pumping. The laser generated 10.14 W of average output power with the pulse width of 16 ps at the repetition rate of 85.2 MHz. To the best of our knowledge this is the highest average output power ever obtained from any of the SESAM mode-locked Nd-doped solid-state lasers that were pumped around 912 nm.
Download or read book Passively Mode locked Diode pumped Yb CaF2 Oscillator written by Yang Yu and published by LAP Lambert Academic Publishing. This book was released on 2014-12-18 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Passively modelocked diode-pumped solid-state lasers based on semiconductor saturable absorber mirrors and Kerr lens mode-locking which have demonstrated good performance in terms of pulse duration, peak power, pulse repetition rates and maintainability. Yb3+:CaF2 has been recognized as a good candidate for a highly efficient high power femtosecond laser. In this thesis, a passively mode-locked diode-pumped Yb3+:CaF2 oscillator has been developed. In the case of the SESAM mode-locking cavity, energetic Q-switched modelocked laser pulses were generated. A Kerr-lens mode-locked oscillator was constructed for continuous-wave modelocking operations by incorporating an additional optical element with an enhanced nonlinear Kerr coefficient, which represents the first such investigation for an Yb3+:CaF2 oscillator to our best knowledge. A 2-pulse per round trip KLM operation was obtained with 970 mW output power at 10 W pump and 164 MHz repetition rate. The output spectrum had a FWHM of 3 nm and centered at 1053 nm.
Download or read book High Speed Diode Lasers written by Sergei A Gurevich and published by World Scientific. This book was released on 1998-01-15 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is composed of seven invited papers which present the current status of high speed diode lasers. Fast carrier and photon dynamics in directly modulated MQW lasers is analyzed and novel design approaches are considered which were critical for the demonstration and record of 40 GHz modulation bandwidth. Attention is centered on the challenges in creation of high speed and low chirp single mode DFB lasers. Recent progress in mode-locked diode lasers is covered, specifically by the examples of 160 fs pulse generation and appearance of microwave pulse repetition rates. Future trends in increasing of high speed laser performance are also examined.
Download or read book Continuous wave Broadly Tunable Diode Laser Array pumped Mid infrared Cr2 CdSe Laser written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ultrafast Lasers written by Martin E. Fermann and published by CRC Press. This book was released on 2002-10-25 with total page 728 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering high-energy ultrafast amplifiers and solid-state, fiber, and diode lasers, this reference examines recent developments in high-speed laser technology. It presents a comprehensive survey of ultrafast laser technology, its applications, and future trends in various scientific and industrial areas. Topics include: micromachining applications for metals, dielectrics, and biological tissue; advanced electronics and semiconductor processing; optical coherence tomography; multiphoton microscopy; optical sampling and scanning; THz generation and imaging; optical communication systems; absolute phase control of optical signals; and more.
