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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

New methods to generate wavelength-tunable pulses from semiconductor and fiber lasers using the dispersion tuning approach.

January 2000 (has links)
Lee Ka-lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract --- p.ii / Acknowledgment --- p.v / Table of contents --- p.vi / List of figure --- p.viii / Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- Generation of picosecond pulses from semiconductor laser and fiber laser --- p.2 / Chapter 1.2. --- Wavelength tunable pulse generated from semiconductor laser --- p.5 / Chapter 1.3. --- Wavelength tunable pulse generated from erbium doped fiber laser --- p.7 / Chapter 1.4. --- Structure of the thesis --- p.8 / Chapter 2. --- Principles and Theories --- p.13 / Chapter 2.1. --- Principle of dispersion tuning --- p.15 / Chapter 2.1.1. --- Dependence on the strength of dispersion --- p.16 / Chapter 2.1.2. --- Wavelength selection in time domain --- p.18 / Chapter 2.1.3. --- Compensated dispersion tuning in a dispersion balanced fiber ring --- p.20 / Chapter 2.2. --- Optical gating using Nonlinear Optical Loop Mirror (NOLM) incorporated with nonlinear element --- p.22 / Chapter 2.3. --- Principle of compensated dispersion tuning in harmonically mode- locked fiber laser incorporated with linearly chirped fiber grating (LCFG) --- p.26 / Chapter 2.4. --- Principle of compensated dispersion tuning in self-seeding configuration --- p.29 / Chapter 2.5. --- Principle of dual-wavelength operation in harmonically mode-locked fiber laser --- p.31 / Chapter 3. --- Preliminarily experimental study --- p.33 / Chapter 3.1. --- Wavelength selection using strong and weak dispersive medium --- p.34 / Chapter 3.2. --- NOLM as a fast optical modulator --- p.38 / Chapter 4. --- Self-compensated dispersion-tuning in mode-locked fiber laser using bi- directional transit in a linearly chirped fiber grating --- p.41 / Chapter 4.1. --- Introduction --- p.42 / Chapter 4.2. --- Experimental Details --- p.43 / Chapter 4.3. --- Results and discussion --- p.47 / Chapter 4.4. --- Summary --- p.54 / Chapter 5. --- Generation of wavelength tunable pulses from a self-seeded semiconductor laser using an optically controlled Nonlinear Optical Loop Modulator (NOLM) incorporated with a Semiconductor Optical Amplifier (SOA) --- p.56 / Chapter 5.1. --- Introduction --- p.57 / Chapter 5.2. --- Experimental Details --- p.58 / Chapter 5.3. --- Results and discussion --- p.64 / Chapter 5.4. --- Summary --- p.71 / Chapter 6. --- Alternate and Simultaneous Generation of 1 GHz Dual-Wavelength Pulses from an Electrically-Tunable Harmonically Mode-locked Fiber Laser --- p.74 / Chapter 6.1. --- Introduction --- p.75 / Chapter 6.2. --- Experimental Details --- p.76 / Chapter 6.3. --- Results and discussion --- p.80 / Chapter 6.4. --- Summary --- p.87 / Chapter 7. --- Conclusion and Future works --- p.89 / Chapter 7.1. --- Conclusion --- p.89 / Chapter 7.2. --- Future works --- p.93 / Appendix --- p.A-l / List of Publication --- p.A-l
112

Tunable multiwavelength picosecond pulses generated from a fabry-perot laser diode.

January 1998 (has links)
by Sui-Pan Yam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references. / Abstract also in Chinese. / Acknowledgements --- p.V / Abstract --- p.VI / Chapter Chapter 1 --- Introduction --- p.1-1 / Chapter 1.1) --- Tunable Multi-Wavelength Optical Sources --- p.1 -1 / Chapter 1.2) --- All-Optical Switching --- p.1 -3 / Chapter 1.2.1) --- Nonlinear Effect / Chapter 1.2.2) --- Special Design of the Laser Structure / Chapter 1.2.3) --- Self-Injection Seeding of Fabry-Perot Laser Diode / Chapter 1.3) --- About This Project --- p.1-6 / Chapter Chapter 2 --- Basic Theory --- p.2-1 / Chapter 2.1) --- Mechanism of Gain-Switching --- p.2-1 / Chapter 2.1.1) --- General Description / Chapter 2.1.2) --- "Optical Pulsewidth, Spectra, and Frequency Chirping of Gain-Switched Pulses" / Chapter 2.2) --- Mechanism of Self-Injection Seeding --- p.2-8 / Chapter 2.2.1) --- General Description / Chapter 2.2.2) --- Dynamics of Single-Mode Formation / Chapter 2.2.3) --- Frequency Evolution of the Laser Diode for Cavity Mode Selection / Chapter 2.2.4) --- Turn-On Delay Time Jitter (TOJ) / Chapter 2.3) --- Mechanism of Injection Seeding --- p.2-17 / Chapter 2.3.1) --- General Description / Chapter 2.3.2) --- The Model of Weak Injection / Chapter 2.3.3) --- The Model of Strong Injection / Chapter Chapter 3 --- Single- and Multi-wavelength Optical Pulses Generated by a Diffraction Grating --- p.3-1 / Chapter 3.1) --- Introduction --- p.3-1 / Chapter 3.2) --- Basic Principle --- p.3-2 / Chapter 3.3) --- Experimental Setup --- p.3-5 / Chapter 3.4) --- Results and Discussion --- p.3-7 / Chapter 3.4.1) --- Spectral Characteristics Analysis / Chapter 3.4.2) --- Individually Access of the Four-Wavelength Output / Chapter 3.4.3) --- The Optical Pulsewidth Characteristics / Chapter 3.4.4) --- Discussion / Chapter 3.5) --- Summary --- p.3-14 / Chapter Chapter 4 --- Using a Highly Dispersive Fiber for Tunable Multi-Wavelength Pulse Generation --- p.4-1 / Chapter 4.1) --- Introduction --- p.4-1 / Chapter 4.2) --- Basic Principle --- p.4-2 / Chapter 4.3) --- Experimental Setup --- p.4-5 / Chapter 4.4) --- Experimental Results --- p.4-7 / Chapter 4.4.1) --- Spectral and Temporal Characteristics / Chapter 4.4.2) --- Wavelength Tuning / Chapter 4.4.3) --- Individually Access of Two Wavelength Channels / Chapter 4.4.4) --- Multi-Wavelength Generation / Chapter 4.5) --- Summary --- p.4-13 / Chapter Chapter 5 --- Comparison of Two Self-Seeding Configurations --- p.5-1 / Chapter 5.1) --- Introduction --- p.5-1 / Chapter 5.2) --- Polarization Sensitivity --- p.5-1 / Chapter 5.3) --- Stability --- p.5-2 / Chapter 5.4) --- Tunability --- p.5-2 / Chapter 5.5) --- Simplification --- p.5-3 / Chapter 5.6) --- Summary of the advantages and disadvantages of Two Configurations --- p.5-4 / Chapter Chapter 6 --- All-Optical Wavelength Switching achieved by Self-Seeding and External Injection-Seeding --- p.6-1 / Chapter 6.1) --- Introduction --- p.6-1 / Chapter 6.2) --- Experimental Setup --- p.6-2 / Chapter 6.3) --- Results and Discussion --- p.6-4 / Chapter 6.3.1) --- Spectral Characteristics / Chapter 6.3.2) --- The Optical Pulsewidth / Chapter 6.3.3) --- The Optical Switching Behaviors / Chapter 6.3.4) --- The Detail Information of Switching / Chapter 6.3.5) --- Optical Power / Chapter 6.4) --- Summary --- p.6-10 / Chapter Chapter 7 --- A Novel Self-Injection Seeding Scheme --- p.7-1 / Chapter 7.1) --- Introduction --- p.7-1 / Chapter 7.2) --- Basic Principle --- p.7-2 / Chapter 7.3) --- Experimental Setup --- p.7-9 / Chapter 7.4) --- Results and Discussion --- p.7-11 / Chapter 7.4.1) --- Spectral and Temporal Characterizations of Two-Wavelength Switching / Chapter 7.4.2) --- Different Wavelength Selection / Chapter 7.4.3) --- Operation Frequency Against the Fiber Length / Chapter 7.4.4) --- Multi-Wavelength Generation / Chapter 7.5) --- Discussion --- p.7-20 / Chapter 7.6) --- Summary --- p.7-22 / Chapter Chapter 8 --- Comparison of Switching Methods --- p.8-1 / Chapter 8.1) --- Introduction --- p.8-1 / Chapter 8.2) --- Switching between Self-Seeding and Injection-Seeding --- p.8-1 / Chapter 8.3) --- Switching by Self-Seeding of a F-P Laser Diode --- p.8-2 / Chapter 8.4) --- Summary --- p.8-3 / Chapter Chapter 9 --- Conclusion --- p.9-1 / References / Figure Captions / Appendix 一 Equipment Descriptions / List of Accepted and Submitted Publications
113

Generation and characterization of tunable multi-wavelength continuous-wave and picosecond-pulsed outputs from a semiconductor laser. / CUHK electronic theses & dissertations collection

January 1998 (has links)
by Ka-Suen Lee. / "June 1998." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
114

Photon manipulation of electron transportation in Chlamydomonas reinhardtii algae using semiconductor lasers

Al-Yasiri, Sadiq Jafar Khayoun January 2018 (has links)
The aim of this research was to increase the rate of cell division in algae by exploring the effect of combinations of lasers of various wavelengths. Literature search has identified a gap in knowledge of the potential for increase in efficiency of the electron transition between photosystem II and photosystem I. This through the use of several wavelengths of blue and or red lasers, including 405 nm, 450, and 473 nm, 635 nm, 650 nm, 680 nm, 685 nm and 700 nm to generate photons with energies more closely matching the absorption spectra of algae receptors known as pigments. This investigation underpins the realisation that photons emanating from a specific laser are absorbed by algae pigments because there is a much closer match between the emission spectrum of the laser and the absorption spectrum of the pigments within the photosystems of algae. This research examined all of the available laser wavelengths in particular combinations; the resultant data contributed to the assembly of a matrix that illustrates the most appropriate laser combinations that promote cell division within algae. Chlamydomonas reinhardtii algae cells successfully grew and divided under exposure to both the blue laser, red laser and that of white light LED when each was applied individually or combined in a sequence. The order of the sequence of using the red and blue lasers in specific cases was important. The pH was maintained between 6.9 and 7.7, with temperatures maintained between 19.00 and 25.00 ºC. For the blue lasers, the laboratory results were as follows, (irradiation time was 12 hours every time): • 405 nm blue laser produced 1.8 x cell division of the white light LED. • For 450 nm blue laser: the white light LED produced 1.5 x cell division of the blue laser 450 nm. • 473 nm blue laser produced 2 x cell division of the white light LED. • 405 nm blue laser produced 3.6 x cell division of natural day light. • 450 nm blue laser produced 1.4 x cell division of natural day light. • 473 nm blue laser produced 4 x cell division of natural day light. For the red lasers, the laboratory results were as follows, (irradiation time was 12 hours every time): • For 635 nm red laser: the white light LED produced 4 x cell division of the red laser 635 nm. • 650 nm red laser produced 1.96 x cell division of the white light LED. • 680 nm red laser produced 2.3 x cell division of the white light LED. • For 685 nm red laser: white light LED produced 1.22 x cell division of the red laser 685 nm. • 700 nm red laser produced 1.35 x cell division of the white light LED. • For 635 nm red laser: the natural day light produced 2 x cell division of the red laser 635 nm. • 650 nm red laser produced 3.9 x cell division of natural day light. • 680 nm red laser produced 4.6 x cell division of natural day light. • 685 nm red laser produced 1.6 x cell division of natural day light. • 700 nm red laser produced 2.7 x cell division of natural day light. For the combination of blue and red lasers, the laboratory results were as follows, (irradiation time was 12 hours every time): • First combination: 405 nm blue laser followed by a combination of 680 nm and 700 nm red lasers produced 4.86 x cell division of the white light LED. • Second combination: 473 nm blue laser followed by a combination of 680 nm and 700 nm red lasers produced 4.66 x cell division of the white light LED. • Third combination: a combination of 680 nm and 700 nm red lasers produced 4.43 x cell division of the white light LED.
115

Luminescent properties of zinc-blende ZnCdSe =: 閃鋅礦結構ZnCdSe的螢光性質. / 閃鋅礦結構ZnCdSe的螢光性質 / Luminescent properties of zinc-blende ZnCdSe =: Shan xin kuang jie gou ZnCdSe de ying guang xing zhi. / Shan xin kuang jie gou ZnCdSe de ying guang xing zhi

January 1996 (has links)
by Ng Po Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 57-59). / by Ng Po Yin. / Acknowledgments --- p.I / Abstract --- p.II / Table of contents --- p.III / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Interest in ZnxCd1-xSe/InP --- p.1 / Chapter 1.2 --- Our work --- p.2 / Chapter 1.3 --- Usefulness of PL --- p.4 / Chapter 1.4 --- Growth conditions of ZnSe/GaAs and ZnxCd1-x/InP --- p.4 / Chapter 1.5 --- Purposes of studying ZnSe/GaAs --- p.5 / Chapter 1.6 --- Inhomogeneity of ZnxCd1-xSe/InP --- p.5 / Chapter Chapter 2 --- Experimental setup and procedures --- p.7 / Chapter 2.1 --- Experimental setup --- p.7 / Chapter 2.2 --- Measurements performed --- p.10 / Chapter 2.3 --- Experimental procedures --- p.10 / Chapter Chapter 3 --- Results and discussion --- p.12 / Chapter 3.1 --- RT and 9K PL of ZnSe/GaAs --- p.12 / Chapter 3.2 --- "Excitation power density dependent, RT and 9K PL of ZnxCd1-xSe/InP" --- p.20 / Chapter 3.3 --- Temperature dependent PL of ZnSe/GaAs and ZnxCd1-xSe/InP --- p.45 / Chapter Chapter 4 --- Conclusions and future work --- p.55 / References --- p.57
116

Ultrashort optical pulses from laser diode and erbium doped fibers.

January 1997 (has links)
Tong Yu Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references. / Abstract --- p.i / Acknowledgments --- p.ii / Table of Contents --- p.iii / Chapter (1) --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Overview of the Thesis --- p.2 / References --- p.4 / Chapter (2) --- Review of Ultrashort Pulse Generation and Pulsewidth Measurement --- p.5 / Chapter 2.1 --- Introduction --- p.5 / Chapter 2.2 --- Q-switching --- p.5 / Chapter 2.3 --- Gain-switching --- p.8 / Chapter 2.4 --- Mode-locking --- p.11 / Chapter 2.4.1 --- Active mode-locking --- p.12 / Chapter 2.4.2 --- Passive mode-locking --- p.13 / Chapter 2.5 --- Optical Pulse Compression --- p.15 / Chapter 2.6 --- Pulsewidth Detection Methods --- p.18 / Chapter 2.6.1 --- Streak camera --- p.18 / Chapter 2.6.2 --- Photodetector and sampling oscilloscope --- p.20 / Chapter 2.6.3 --- Nonlinear autocorrelator --- p.21 / Chapter 2.6.4 --- Other techniques --- p.24 / References --- p.25 / Chapter (3) --- Erbium Doped Fiber Amplifier and Active Mode-locking --- p.28 / Chapter 3.1 --- Introduction --- p.28 / Chapter 3.2 --- Erbium Doped Fiber Amplifier --- p.28 / Chapter 3.2.1 --- Background --- p.28 / Chapter 3.2.2 --- Experiment --- p.31 / Chapter 3.3 --- Additive Pulse Mode-locking --- p.35 / Chapter 3.4 --- Active Mode-locking --- p.37 / Chapter 3.4.1 --- Background --- p.37 / Chapter 3.4.2 --- Experiment and result --- p.38 / Chapter 3.4.3 --- Discussion --- p.43 / Chapter 3.5 --- Chapter Summary --- p.46 / References --- p.46 / Chapter (4) --- Passive Mode-locking of Erbium Doped Fiber Laser --- p.49 / Chapter 4.1 --- Introduction --- p.49 / Chapter 4.2 --- Background --- p.49 / Chapter 4.3 --- Experimental Setup --- p.51 / Chapter 4.4 --- Initialing Mode-locking --- p.54 / Chapter 4.5 --- Experimental Result --- p.55 / Chapter 4.5.1 --- Real time pulse train --- p.55 / Chapter 4.5.2 --- Autocorrelation trace --- p.57 / Chapter 4.5.3 --- RF spectrum --- p.58 / Chapter 4.5.4 --- Optical spectrum --- p.59 / Chapter 4.5.5 --- Time-bandwidth product --- p.60 / Chapter 4.5.6 --- Output power --- p.61 / Chapter 4.6 --- Discussion --- p.63 / Chapter 4.6.1 --- Linear pulse broadening --- p.63 / Chapter 4.6.2 --- Cavity oscillation --- p.65 / Chapter 4.6.3 --- Pump power hysteresis --- p.66 / Chapter 4.6.4 --- Sideband generation --- p.67 / Chapter 4.6.5 --- Spectral distortion --- p.68 / Chapter 4.7 --- Chapter Summary --- p.71 / References --- p.72 / Chapter (5) --- Application of Ultrashort Optical Pulses from Figure Eight Laser --- p.74 / Chapter 5.1 --- Introduction --- p.74 / Chapter 5.2 --- Dispersion Measurement --- p.74 / Chapter 5.2.1 --- Introduction --- p.74 / Chapter 5.2.2 --- Background --- p.75 / Chapter 5.2.3 --- Experiment and result --- p.76 / Chapter 5.2.4 --- Discussion and conclusion --- p.80 / Chapter 5.3 --- Time Domain Spectral Estimation --- p.82 / Chapter 5.3.1 --- Introduction --- p.82 / Chapter 5.3.2 --- Background --- p.82 / Chapter 5.3.3 --- Experiment and result --- p.83 / Chapter 5.3.4 --- Discussion --- p.88 / Chapter 5.4 --- Ultrashort Pulse Amplification --- p.89 / Chapter 5.4.1 --- Introduction --- p.89 / Chapter 5.4.2 --- Background --- p.89 / Chapter 5.4.3 --- Experiment and result --- p.92 / Chapter 5.4.4 --- Discussion and conclusion --- p.95 / References --- p.96 / Chapter (6) --- Picosecond Pulse Generation from Semiconductor Laser Diodes --- p.99 / Chapter 6.1 --- Introduction --- p.99 / Chapter 6.2 --- Gain-switching --- p.99 / Chapter 6.2.1 --- Experiment using commercial laser diodes --- p.99 / Chapter 6.2.2 --- Repetition rate multiplication --- p.102 / Chapter 6.2.3 --- Pulse compression with HDSF --- p.107 / Chapter 6.2.4 --- Fiber loop compressor --- p.110 / Chapter 6.3 --- Active or Hybrid Mode-locking --- p.112 / Chapter 6.3.1 --- Introduction --- p.112 / Chapter 6.3.2 --- Laser structure --- p.113 / Chapter 6.3.3 --- Experiment and result --- p.113 / Chapter 6.3.4 --- Discussion and conclusion --- p.116 / Chapter 6.4 --- Amplifier Modulation --- p.117 / Chapter 6.4.1 --- Introduction --- p.117 / Chapter 6.4.2 --- Experiment and result --- p.118 / Chapter 6.5 --- Wavelength Tuning --- p.120 / Chapter 6.5.1 --- Introduction --- p.120 / Chapter 6.5.2 --- Experiment and result --- p.121 / Chapter 6.5.3 --- Conclusion --- p.123 / Chapter 6.6 --- Chapter Summary --- p.124 / References --- p.124 / Chapter (7) --- Conclusion --- p.126 / Chapter 7.1 --- Summary of the Research --- p.126 / Chapter 7.1.1 --- Fiber lasers --- p.126 / Chapter 7.1.2 --- Diode lasers --- p.128 / Chapter 7.2 --- Further Study --- p.129 / Appendix I Project Instrumentation --- p.A-l / Appendix II Curve Fitting Program for the SHG Autocorrelation Trace --- p.A-8 / Appendix III Experiment Setup of Figure Eight Laser --- p.A-12 / "Appendix IV Curve Fitting Program for Determination of Second Order Dispersion, dD/dλ" --- p.A-14 / Appendix V 1.3 μm two sections DFB/TA Laser Diode Chips --- p.A-17 / Appendix VI Publication List --- p.A-l9
117

Nonlinear dynamics and polarization properties of externally driven semiconductor lasers

Sciamanna, Marc 22 January 2004 (has links)
Voir fichier joint "1ère partie"
118

GaAs-based long-wavelength quantum dot lasers /

Park, Gyoungwon, January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 89-95). Available also in a digital version from Dissertation Abstracts.
119

Theoretical study of GaAs-based quantum dot lasers and microcavity light emitting diodes

Huang, Hua 28 August 2008 (has links)
Not available / text
120

Improvement of semiconductor laser diodes' characteristics by using diffused quantum wells structure

盧志偉, Lo, Chi-wai. January 1997 (has links)
published_or_final_version / Electrical and Electronic Engineering / Master / Master of Philosophy

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