Showing papers on "Fiber laser published in 1992"
TL;DR: In this paper, the authors present a detailed theoretical and experimental investigation of the nonlinear dynamics of a semiconductor laser with optical feedback, showing that the coherence collapsed state is a chaotic attractor and that chaos is reached for increasing feedback level through a quasi-periodic route interrupted by frequency locking.
Abstract: The authors present a detailed theoretical and experimental investigation of the nonlinear dynamics of a semiconductor laser with optical feedback. The results show that the coherence collapsed state is a chaotic attractor and that chaos is reached for increasing feedback level through a quasi-periodic route interrupted by frequency locking. Furthermore, the coexistence of two attractors, associated with the same external cavity mode, but having different relaxation oscillation frequencies, is demonstrated and explained. >
523 citations
TL;DR: In this paper, nonlinear birefringence effects in a fiber ring laser cavity have been exploited to produce selfstarting, passive mode-locking to give 1.5 ps soliton pulses.
Abstract: Nonlinear birefringence effects in a fibre ring laser cavity have been exploited to produce selfstarting, passive mode-locking to give 1.5 ps soliton pulses.
451 citations
TL;DR: In this paper, the first observation of discrete jumps in the power output of an all-fibre passively mode-locked laser was reported and the discontinuities were associated with quantisation of the energy of the pulses circulating within the laser cavity.
Abstract: For the first time the observation of discrete jumps in the power output of an all-fibre passively mode-locked laser is reported. The discontinuities are associated with quantisation of the energy of the pulses circulating within the laser cavity.
243 citations
TL;DR: A single-mode linear-cavity fiber laser that utilizes intracore Bragg reflectors for cavity feedback has been continuously tuned, without mode hopping, when both the gratings and enclosed fiber are stretched uniformly.
Abstract: A single-mode linear-cavity fiber laser that utilizes intracore Bragg reflectors for cavity feedback has been continuously tuned, without mode hopping, when both the gratings and enclosed fiber are stretched uniformly. Continuous tuning is achieved in a 1.54-microm erbium fiber laser since the change in the reflected wavelength from a Bragg reflector tracks the change in the cavity resonance wavelength.
223 citations
TL;DR: The first single-wavelength pumped, CW, room-temperature, blue upconversion laser was reported in this paper, which used Tm/sup 3+/ as the active ion in a fluorozirconate glass fibre.
Abstract: The authors report what they believe to be the first single-wavelength pumped, CW, room-temperature, blue upconversion laser. This 480 nm laser uses Tm/sup 3+/ as the active ion in a fluorozirconate glass fibre. Up to 60 mW of output power has been observed with a slope efficiency of 18% with respect to coupled pump power.<
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197 citations
TL;DR: Very short erbium-fibre laser with holographically written gratings in the core was reported in this article, achieving an output power of 181 mu W from a 2 cm long diode-pumped laser.
Abstract: Very short erbium-fibre lasers with holographically written gratings in the erbium-doped fibre core are reported. An output power of 181 mu W was obtained from a 2cm long diode-pumped laser. A 1 cm long diode pumped laser had an output power of 57 mu W. As would be expected for such short cavity lengths, these lasers are robustly singlemode.<
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169 citations
TL;DR: It is shown that a saturable absorber and a frequency limiter are required for the ring laser to self-start, i.e., to mode lock from initial noise and to operate stably, and that nonlinear polarization rotation with polarization selectivity inside the ring can act as a saturables absorber.
Abstract: A fiber ring laser that can produce nearly transform-limited soliton pulses is simulated. This laser has an erbium-doped optical-fiber amplifier and allows wavelength tuning through the interplay of fiber chromatic dispersion and the round-trip delay time of the laser. We show that a saturable absorber and a frequency limiter are required for the ring laser to self-start, i.e., to mode lock from initial noise and to operate stably. We also show that nonlinear polarization rotation with polarization selectivity inside the ring can act as a saturable absorber.
166 citations
TL;DR: In this article, an all-solid-state passively mode-locked neodymium glass fiber laser is investigated by employing characterization techniques in the time, optical, and radio-frequency domains.
Abstract: Pulse formation in an all-solid-state passively mode-locked neodymium glass fiber laser is investigated by employing characterization techniques in the time, optical, and radio-frequency domains. The pulses are generated by a combination of passive amplitude modulation arising from nonlinear polarization evolution and passive frequency modulation due to quasi-soliton-like pulse shaping. Several distinct operation modes for ultrashort pulse generation are described and pulses as short as 38 fs are directly generated in the cavity. >
150 citations
CNET1
TL;DR: In this paper, an erbium doped fluorozirconate fiber pumped at 0.97μm was used to achieve green power and slope efficiency against launched pump power of 15% at room temperature.
Abstract: 50mW of green power and slope efficiency against launched pump power of 15% have been obtained at room temperature in an erbium doped fluorozirconate fibre pumped at 0.97μm. Lasing tunability domain, pump wavelength tunability and the role of colasing at 1.55μm are described.
135 citations
TL;DR: The numerical simulations indicate that stable stationary trains of pulses may be formed in the cavity, independent of the sign of the dispersion, and simple analytical expressions for the sideband gain are obtained by using an average pulse formalism.
Abstract: A synchronously pumped modulational-instability ring laser with a nonlinear dispersive fiber can be operated in both the anomalous and the normal dispersion regimes. We obtain simple analytical expressions for the sideband gain in the cavity by using an average pulse formalism. The numerical simulations indicate that stable stationary trains of pulses may be formed in the cavity. This is independent of the sign of the dispersion.
134 citations
TL;DR: The response of an Nd-doped optical fiber laser to modulation of the pump power reveals that the polarization of the laser light plays an important role in the linear and nonlinear dynamics of this laser.
Abstract: The response of an Nd-doped optical fiber laser to modulation of the pump power reveals that the polarization of the laser light plays an important role in the linear and nonlinear dynamics of this laser. Experiments have been carried out under pulsed or sinusoidal modulation of the pump power as well as in the continuous-wave regime. Most of the observed phenomena may be interpreted in the framework of a theory of the two-mode laser in which each mode is associated with one polarization eigenstate of the laser. Effects such as the appearance of slow modes and antiphase behavior have also been observed. A model of a two-mode laser including spontaneous emission is theoretically and numerically analyzed. It reproduces well most of the experimental findings.
TL;DR: In this article, an optical data stream is used to mode-lock a fiber laser at (or an integer multiple of) the line rate, where a length of data transmission fibre is shared with the fiber laser and mode locking occurs through the process of cross-phase modulation.
Abstract: A novel all-optical clock recovery scheme in which an optical data stream is used to mode-lock a fibre laser at (or an integer multiple of) the line rate is experimentally demonstrated. A length of data transmission fibre is shared with the fibre laser and mode locking occurs through the process of crossphase modulation.
TL;DR: A theoretical model is developed to describe the self-mixing signals as a function of the amount of feedback into the laser and the distance from the laser to the moving object.
Abstract: A laser Doppler velocimeter that consists of a semiconductor laser coupled to a fiber and that uses the self-mixing effect is presented. The velocimeter can be used for solids and fluids. A theoretical model is developed to describe the self-mixing signals as a function of the amount of feedback into the laser and the distance from the laser to the moving object. Good agreement is found between this theory and measurements.
TL;DR: In this paper, a stabilisation scheme for a mode-locked erbium fiber laser which relies on locking the pulse phase with that of the drive source is reported. And the first bit error rate (BER) measurement on such a laser has been demonstrated.
Abstract: A stabilisation scheme for a mode-locked erbium fibre laser which relies on locking the pulse phase with that of the drive source is reported. Using this scheme, the first bit-error-rate (BER) measurement on such a laser has been demonstrated. Stable error free operation at 2Gbit/s and a received power of 26dBm has been observed over a period of >0.5h showing the potential suitability of the laser as a transmission source.
TL;DR: In this paper, the design constraints required to achieve single-longitudinal mode operation from a standing-wave, homogeneously broadened, three-level, fiber laser which utilizes intracore Bragg reflectors for cavity feedback are presented.
Abstract: The design constraints required to achieve single-longitudinal-mode operation from a standing-wave, homogeneously broadened, three-level, fiber laser which utilizes intracore Bragg reflectors for cavity feedback are presented. In particular, a closed-form solution to the laser rate equations is found which bounds the region in which only single longitudinal mode operation is supported. The principal resonator geometry to be considered is a two-reflector cavity which utilizes only Bragg reflectors for feedback. Analytical and experimental results are discussed. >
TL;DR: In this article, a 200-stripe linear diode-laser array is geometrically transformed into a two-dimensional, symmetric virtual source with symmetric divergence to end pump a Nd:YAG laser.
Abstract: A 200-stripe linear diode-laser array is geometrically transformed into a two-dimensional, symmetric virtual source with symmetric divergence to end pump a Nd:YAG laser. The geometrical transformation is performed by two planes of diffractive optical elements separated by a 2.6-cm gap. Discounting optical losses, a TEM/sub 00/ mode slope efficiency of 56% is demonstrated. Methods of increasing the throughput efficiency of the diffractive elements (currently approximately 50% per element,) are explored. A theoretical model for estimating the maximum useful pump array size in longitudinally pumped rod and fiber lasers shows that this pump geometry is close to optimum. >
Patent•
09 Sep 1992TL;DR: In this paper, a system for coupling laser radiation at a high power to an optical fiber while dissipating heat from scattered laser and optical pump radiation was proposed, including a protective ferrule surrounding a portion of the optical fiber.
Abstract: A system for coupling laser radiation at a high power to an optical fiber while dissipating heat from scattered laser and optical pump radiation, including an optical fiber, a protective ferrule surrounding a portion of the optical fiber extending from the input face of the optical fiber and welded to the fiber in the region of the input face and otherwise separated from the fiber by an air space, and a holder surrounding the ferrule to absorb scattered radiation and dissipate heat.
TL;DR: In this paper, the authors derived the gain for mixed Stokes and anti-Stokes waves propagating in a birefringent fiber under the combined action of parametric four-photon mixing and Raman scattering, for different types of phase matching.
Abstract: We derive the gain for mixed Stokes and anti-Stokes waves propagating in a birefringent fiber in the presence of an intense pump wave, under the combined action of parametric four-photon mixing and Raman scattering, for different types of phase matching. We discuss the conditions for the suppression or the enhancement of the Raman gain as a function of the linear mismatch and of the sideband detuning, owing to coupling between Stokes and anti-Stokes components of the growing wave. We confirm the analytical predictions of the linearized analysis with the numerical solution of the coupled nonlinear Schrodinger equations, including the contribution of the tensorial Raman response of the fiber.
Book•
01 Feb 1992
TL;DR: In this article, the authors introduce the idea of a laser and how to use it in a variety of applications, such as low-power printing, high-power computing, and high-dimensional sensing.
Abstract: Preface. CHAPTER 1 Introduction and Overview. 1.1 The Idea of the Laser. 1.2 What is a Laser? 1.3 Laser Materials and Types. 1.4 Optical Properties of Laser Light. 1.5 How Lasers are Used. 1.6 What Have We Learned? CHAPTER 2 Physical Basics. 2.1 Electromagnetic Waves and Photons. 2.2 Quantum and Classical Physics. 2.3 Interactions of Light and Matter. 2.4 Basic Optics and Simple Lenses. 2.5 What Have We Learned? CHAPTER 3 How Lasers Work. 3.1 Building a Laser. 3.2 Producing a Population Inversion. 3.3 Resonant Cavities. 3.4 Laser Beams and Resonance. 3.5 Wavelength Selection and Tuning. 3.6 Laser Excitation Techniques. 3.7 What Have We Learned? CHAPTER 4 Laser Characteristics. 4.1 Coherence. 4.2 Laser Wavelengths. 4.3 Behavior of Laser Beams. 4.4 Laser Power. 4.5 Laser Efficiency. 4.6 Duration of Emission. 4.7 Polarization. 4.8 What Have We Learned? CHAPTER 5 Optics and Laser Accessories. 5.1 Classical Optical Devices. 5.2 Transparent Optical Materials. 5.3 Optical Surfaces, Coatings and Filters. 5.4 Nonlinear Optics. 5.5 Beam Intensity and Pulse Control. 5.6 Beam Direction and Propagation. 5.7 Mounting and Positioning Equipment. 5.8 Optical Measurement. 5.9 What Have We Learned? CHAPTER 6 Types of Lasers. 6.1 Laser Oscillators and Optical Amplifiers. 6.2 Laser Media. 6.3 The Importance of Gain. 6.4 Broadband and Wavelength-Tunable Lasers. 6.5 Laser-Like Light Sources. 6.6 What Have We Learned? CHAPTER 7 Gas Lasers. 7.1 The Gas Laser Family. 7.2 Gas-Laser Basics. 7.3 Helium-Neon Lasers. 7.4 Argon- and Krypton-Ion Lasers. 7.5 Metal-Vapor Lasers. 7.6 Carbon Dioxide Laser. 7.7 Excimer Lasers. 7.8 Chemical Lasers. 7.9 Other Gas Lasers. 7.10 What Have We Learned? CHAPTER 8 Solid-State and Fiber Lasers. 8.1 What is a Solid-State Laser? 8.2 Solid-State Laser Materials. 8.3 Optical Pumping. 8.4 Ruby Lasers. 8.5 Neodymium Lasers. 8.6 Vibronic and Tunable Solid-State Lasers. 8.7 Erbium and Other Eye-Safe Laser. 8.8 Rare-Earth-Doped Fiber Lasers. 8.9 Rare-Earth-Doped Fiber Amplifiers. 8.10 Raman Fiber Lasers and Amplifiers. 8.11 What Have We Learned? CHAPTER 9 Semiconductor Diode Lasers. 9.1 Basics of Semiconductor Diode Lasers. 9.2 Semiconductor Basics. 9.3 Light Emission at Junctions. 9.4 Layers and Confinement in Diode Lasers. 9.5 Confinement in the Junction Plane. 9.6 Edge-Emitting Diode Lasers. 9.7 Surface-Emitting Diode Lasers. 9.8 Quantum Wells and Dots. 9.9 Quantum Cascade Lasers. 9.10 Optical Properties of Diode Lasers. 9.11 Diode Laser Materials and Wavelengths. 9.12 Silicon Lasers. 9.13 Packaging and Specialization of Diode Lasers. 9.14 What Have We Learned? CHAPTER 10 Other Lasers and Related Sources. 10.1 Tunable Dye Lasers. 10.2 Extreme-Ultraviolet Sources. 10.3 Free-Electron Lasers. 10.4 Silicon Lasers. 10.5 What Have We Learned? CHAPTER 11 Low-Power Laser Applications. 11.1 Advantages of Laser Light. 11.2 Reading with Lasers. 11.3 Optical Disks and Data Storage. 11.4 Laser Printing and Marking. 11.5 Fiber-Optic Communications. 11.6 Laser Measurement. 11.7 Laser Pointers, Art, and Entertainment. 11.8 Low-Power Defense Applications. 11.9 Sensing and Spectroscopy. 11.10 Holography. 11.11 Other Low-Power Applications. 11.12 What Have We Learned? CHAPTER 12 High-Power Laser Applications. 12.1 High- Versus Low-Power Laser Applications. 12.2 Attractions of High-Power Lasers. 12.3 Materials Working. 12.4 Electronics Manufacturing. 12.5 Three-Dimensional Modeling. 12.6 Laser Medical Treatment. 12.7 Photochemistry and Isotope Separation. 12.8 Laser-Driven Nuclear Fusion. 12.9 High-Energy Laser Weapons. 12.10 Futuristic High-Power Laser Ideas. 12.11 What Have We Learned? CHAPTER 13 Lasers In Research. 13.1 Lasers Open New Opportunities. 13.2 Laser Spectroscopy. 13.3 Manipulating Tiny Objects. 13.4 Atom Lasers and Bose-Einstein Condensates. 13.5 Slow Light. 13.6 Nanoscale Lasers. 13.7 Petawatt Lasers. 13.8 Attosecond Pulses. 13.9 Laser Acceleration. 13.10 Other Emerging Research. 13.11 What We Have Learned. Answers to Quiz Questions. Appendix A: Laser Safety. Appendix B: Handy Numbers and Formulas. Appendix C: Resources and Suggested Readings. Glossary. Index.
01 Feb 1992
TL;DR: The feasibility of using semiconductor laser diodes to pump EDFAs insures that EDFA's are practical devices which will have great impact on optical communications as power boosters, optical repeaters and optical preamplifiers as discussed by the authors.
Abstract: Erbium-doped fiber amplifiers (EDFA’s) operate in the 1.5?m wavelength telecommunications window and have achieved high gain, high output power and near ideal noise performance. The feasibility of using semiconductor laser diodes to pump EDFA’s insures that EDFA’s are practical devices which will have great impact on optical communications as power boosters, optical repeaters and optical preamplifiers.
TL;DR: The first fiber laser operating above 3 mu m at room temperature was reported in this paper, where the first Er/sup 3+/-doped ZBLAN fiber pumped at 655 nm showed CW laser operation around 3.5 mu m.
Abstract: The first fibre laser operating above 3 mu m at room temperature is reported. An Er/sup 3+/-doped ZBLAN fibre pumped at 655 nm shows CW laser operation around 3.5 mu m. >
TL;DR: Recently there has been considerable interest in the field of rare-earth-doped integrated optics because of their potential use in compact and efficient monolithic devices combining the rare- earth laser gain and the large range of integrated optical functions already demonstrated.
Abstract: Recently there has been considerable interest in the field of rare-earth-doped integrated optics because of their potential use in compact and efficient monolithic devices combining the rare-earth laser gain and the large range of integrated optical functions already demonstrated. Recent developments in Nd(3+)-doped and Er(3+)-doped glass and LiNbO(3) waveguide lasers and optical amplifiers, their application, and future prospects are reviewed briefly.
TL;DR: This work proposes and analyzes a passively mode-locked laser based on an active nonlinear directional coupler that should result in stable trains of sub-100-fs pulses.
Abstract: We propose and analyze a passively mode-locked laser based on an active nonlinear directional coupler. Implementation of this concept in a dual-core erbium-doped fiber laser should result in stable trains of sub-100-fs pulses.
TL;DR: Very high-speed, stable picosecond optical pulses are generated from an active harmonic mode-locked Er3+-doped fiber laser with a 16m long polarisation maintaining ring cavity as mentioned in this paper.
Abstract: Very high-speed, stable picosecond optical pulses are generated from an active harmonic mode-locked Er3+-doped fibre laser with a 16m long polarisation maintaining ring cavity. Resultant transform-limited, 3.5–10ps optical pulses with a time-bandwidth product of 0.31–0.33, are analysed at repetition rates from 2 to 20GHz. The authors confirm bit-error-free stable operation at up to 8 Gbit/s.
Patent•
28 Feb 1992TL;DR: An asymmetric hyperbolic microlens on the end of a single-mode optical fiber enhances the fiber's coupling to elliptical laser beams as mentioned in this paper, which is useful to pump erbium-doped fiber amplifiers.
Abstract: An asymmetric hyperbolic microlens on the end of a single-mode optical fiber enhances the fiber's coupling to elliptical laser beams The lenses, with controlled eccentricity ratios, are made by micromachining the end of the fiber with a pulsed CO₂ laser as the fiber is directed, preferably by computer control, about the focused laser beam Coupling efficiencies of 90 percent (-075 dB) have been realized with single transverse mode lasers at a wavelength of 098 µm having an approximately 3 to 1 beam ellipticity With multimode lasers at 148 µm having similar elliptical beams, the asymmetric lenses demonstrate an almost 2 dB increase in coupling efficiency over symmetric hyperbolic microlenses Such lasers are useful to pump erbium-doped fiber amplifiers About 120 mw was coupled from such a laser into single-mode fiber
TL;DR: An experimental verification of the theoretical scaling relationship of the spectral components that are a characteristic of instability in fiber soliton lasers and are dominant when the system length is comparable with the related soliton length is presented.
Abstract: We present an experimental verification of the theoretical scaling relationship of the spectral components that are a characteristic of instability in fiber soliton lasers and are dominant when the system length is comparable with the related soliton length.
TL;DR: A sapphire optical fiber intrinsic Fabry–Perot interferometric sensor is demonstrated that has been demonstrated for temperature measurement and has a resolution of 0.2°C.
Abstract: A sapphire optical fiber intrinsic Fabry–Perot interferometric sensor is demonstrated. A length of multimode sapphire fiber that functions as a Fabry–Perot cavity is spliced to a silica single-mode fiber. The interferometric signals of this sensor are produced by the interference between the reflection from the silica–sapphire fiber splice and the reflection from the free end face of the sapphire fiber. This sensor has been demonstrated for temperature measurement. A resolution of 0.2°C has been obtained over a measurement range of 310°C to 976°C.
11 Dec 1992
TL;DR: In this paper, the authors used a scanning laser polarimeter for quantitative measurements of the retinal nerve fiber layer thickness in vivo, where the measuring beam was focused on the retina and penetrates the birefringent nerve fiber layers.
Abstract: The assessment of the condition of the retinal nerve fiber layer plays an important role for the early detection of blinding eye diseases like glaucoma. We describe the application of a scanning laser polarimeter for quantitative measurements of the retinal nerve fiber layer thickness in vivo. The measuring beam of the scanning laser polarimeter is focused on the retina and penetrates the birefringent nerve fiber layer. The retardation of the light double- passing the nerve fiber layer is proportional to its thickness and is measured at 256 by 256 positions within a field of view of 15 by 15 degrees. The measurement time is less than 1 second. During the measurement, the polarization effects of the anterior segment of the human eye are canceled by a cornea polarization compensator. The retinal retardation values are displayed as a color coded map of the retinal nerve fiber layer thickness distribution.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
TL;DR: In this article, an erbium figure eight all-fibre laser with a fundamental repetition rate of 28.5 MHz was reported and the feedback of light rejected by the nonlinear amplifying loop mirror back into the laser was found to stabilise mode locking enhance startup, shorten the pulse lenght to 275fs, and provide a simple means of multiplying the repetition rate.
Abstract: The operation of an erbium figure eight all-fibre laser with a fundamental repetition rate of 28.5 MHz is reported. The feedback of light rejected by the nonlinear amplifying loop mirror back into the laser is found to stabilise mode locking enhance startup, shorten the pulse lenght to 275fs, and provide a simple means of multiplying the repetition rate.
TL;DR: In this article, the onset of modulation instability in erbium-doped fiber amplifiers was studied through a stability analysis of the underlying nonlinear Schrodinger equation, and it was shown that the existence of gain in EDFAs lowers the threshold for modulation instability considerably compared with the case of undoped fibers.
Abstract: The onset of modulation instability in erbium-doped fiber amplifiers (EDFAs) is studied through a stability analysis of the underlying nonlinear Schrodinger equation. The existence of gain in EDFAs lowers the threshold for modulation instability considerably compared with the case of undoped fibers. Modulation instability generates multiple pulses when a single pulse is amplified. It can also create multiple subpulses in mode-locked fiber lasers, a feature observed experimentally. Numerical simulations show that EDFAs can convert a continuous-wave optical signal into a train of high-repetition rate femtosecond pulses. >