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Showing 1 to 20 of 40 for “"Thulium"”.
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Spectroscopy of thulium doped silica glass
… fibre amplifier. Of the possible candidates, thulium-doped fibre amplifiers appear best suited to serve this need with amplification available from 1460 to 1530 nm. However, the current limitation with these devices is that the amplifying transition can only provide sufficient gain when doped …
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Energy transfer between thulium and holmium in laser hosts
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1993.
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Mode-locking of thulium-doped and Erbium-doped fiber lasers
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.
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Thulium-doped fibre laser in the 2 μm wavelength region for gas sensing
The transition 3F4->3H6 of trivalent Thulium is widely studied for generating lasers at wavelength near 2 μm. For decades, tuneable continuous wave narrow line-width sources in this wavelength region have been proved to be very useful as spectroscopic tools for trace gas detection. Semiconductor …
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Real-time characterization of transient dynamics in thulium-doped mode-locked fiber laser
Thulium (Tm) based high repetition rate compact optical frequency comb sources operating in the 2 µm regime with femtosecond pulse durations enable a wide range of applications such as precise micro-machining, spectroscopy and metrology. Applications such as metrology and spectroscopy rely on the …
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Set up of a short magnetic lens electron spectrometer and investigation of cesium-137 and thulium-170 decay.
The present work contains the discussion on the set up of a short magnetic lens electron spectrometer, and the results of an investigation of the beta decay spectra of Cs137 and Tm170. A short magnetic lens electron spectrometer of about 21cm focal length was set up and used during the course of …
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Operating Regimes and Automated Control of Holmium and Thulium Non-linear Polarisation Rotation Mode-locked Fibre Optic Lasers
… rate of 17 MHz and pulse energy of 3 nJ. A thulium NLPR source was developed to further explore possible automation metrics and characterise a range of additional undesired operating regimes. Automation metrics tested to determine if the laser was continuously mode-locked included …
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Power scaling of Tm:YLF-pumped Ho:YAG lasers
… requirements on the thulium doping concentration in Tm:YLF provided motivation for the preliminary experiments of laser performance characterisation to find the optimum doping concentration. The optimum doping concentration is defined as that which gives the highest …
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New techniques for multiple wavelength fiber laser generation based on edfa and tdfa
… based on erbium doped fiber amplifier (EDFA) or thulium doped fiber amplifier (TDFA). The first study is related to a numerical analysis of Brillouin erbium fiber laser (BEFL). In this study, the elements of EDFA and stimulated Brillouin scattering (SBS) effect are thoroughly investigated. It is …
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A spectroscopic investigation of novel doped glasses for active infrared devices
… decay to the same extent as Cr-doped GLS. Thulium and erbium-doped tin silicate glass-ceramics produced by the sol-gel method were studied for as potential amplifier materials. The addition of tin oxide to these glasses makes them photosensitive and is shown in this work to increase …
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Untersuchung eines diodengepumpten Faserverstärkers mit Emission bei 2 µm
… <br> <br>Dabei werden kurze Laserdiodenpulse in Thulium-dotierten optischen Fasern verstärkt und somit die Vereinigung der Vorteile der direkten elektronischen Kontrolle einer Laserdiode mit dem robusten und leicht zu integrierenden Aufbau eines optischen Fasersystems kombiniert. <br> <br>Nach …
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Rare-earth-doped gallium lanthanum sulphide glasses for mid-infrared fibre lasers
… dysprosium transitions, whereas the 3.8 µm thulium and the 3.9 µm holmium transitions coincide with an atmospheric transmission window. <br/><br/>Co-doping schemes such as thulium/terbium, praseodymium/ytterbium, praseodymium/erbium, and dysprosium/erbium which offer more favourable …
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Environmentally Stable Mode-locked Fibre Lasers in the Near-Infrared
… and 2 µm bands, using ytterbium-, erbium-, and thulium-doped fibre, respectively. From 1 –2 µm, the optical characteristics of silica optical fibre change considerably, giving us an ample landscape to investigate the behaviour high pulse energy (∼ nJ) laser sources in depth. In this thesis we …
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Magnetic and Spintronic Properties of Rare-Earth Iron Garnets
… extensively in recent years. In particular, thulium iron garnet (TmIG) has excited great interest due to record-breaking spin orbit torque-driven domain wall velocities over 2km/s and the presence of the Dzyaloshinskii-Moriya interaction, which stabilizes chiral Néel domain walls. In order to …
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Direct mass measurements beyond the proton drip-line
… 18 neutron-deficient isotopes in the terbium-to-thulium region with relative uncertainties of about 10-8. The masses of nine nuclides were measured for the first time. Four of them (144Ho, 145Ho, 147Tm and 148Tm) were determined to lie beyond the proton drip-line. The data were included into the …
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Dynamics of a Q-switched all-fibre laser
… fibre as the gain section and several lengths of Thulium doped absorber section, which has a relatively faster relaxation time. Through comprehensive experiments and numerical computations we demonstrate two distinct ways in which Q-switched pulses are born, with a subsequent path from regular to …
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A Mathematical Model of the Dynamics of an Optically Pumped Codoped Solid State Laser System
… examined.</p> <p>The laser system consists of thulium and holmium ions in a YAG crystal operated in a Fabrey-Perot cavity. All computer programs were written in FORTRAN and currently run on either an IBM-PC or a DEC VAX 11/750.</p>
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Optical signal generation, stabilization, and manipulation in broadband silicon photonics
… lasers are demonstrated in the C-band. Then, thulium is studied and characterized as a dopant for applications at longer wavelengths. On-chip frequency stability issues are addressed by investigating the thermo-optic characteristics of various CMOS-compatible media. Negative thermo-optic …
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UV-written devices in rare-earth doped silica-on-silicon grown by FHD
… efficiency). <br/><br/>Erbium, ytterbium and thulium doping have been investigated to allow the production of light sources at other wavelengths. Further optimisation is still required to allow lasing to be achieved. Nevertheless, demonstration of y-splitters and Bragg grating fabrication in …
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