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A fundamental formulation of plasmonic nanolasers from Fermi's Golden rule is developed by considering the inhomogeneity and dispersion of the cavity media. A Fabry-Perot nanolaser based on the plasmonic slab waveguide is used as an example and the studies have shown that the power confinement is inappropriate for plasmonic cavity modes.

A charge control model is developed for the transient analysis of the bipolar transistor laser in forward active mode in order to describe the dynamics of electron, photon and charge densities. The analysis of laser switching has shown that the turn-on time is reduced by increasing the base current or decreasing the spontaneous emission lifetime of electrons in the quantum well.

The possible causes of power limitation of nanosecond Nd:glass lasers are analyzed, where small-scale self-focusing is considered to be one of the main causes. A simple analytical dependence is found for an optimal distance between two nonlinear media and the maximum attainable energy in neodymium-phosphate glass lasers with rod amplifiers 10 cm in diameter is 400 J with pulse duration of 1 ns.

Broad-area vertical-cavity surface-emitting lasers (AVCSELs) grown in the antiwaveguiding approach are examined. Results suggest that the conventional AVCSEL device lases in high-order excited modes.

The optimization of microelectromechanical system (MEMS)-tunable vertical-cavity surface-emitting lasers (VCSELs) operating at wavelength around 1.55 m is discussed. Device tuning range, modal frequency splitting, threshold gains and modal selectivity are observed.

Comprehensive models of quantum-cascade (QC) operation were used for examining the thermal and Stark-effect rollover in QC lasers. Stark effect rollover was observed in devices with low thermal resistance and low injector doping levels before reaching the thermal rollover regime.

A new model is used for the calculation of the output characteristics of a fiber Bragg grating (FBG)-stabilized pump-laser module depending on the effective feedback from the grating. Findings reveal the capability of the proposed model in accurately simulating the properties of the wavelength-stabilized pump-laser module.

The nonlinear dynamics of a passive mode-locked fiber laser containing a long period fiber grating are evaluated. Results suggest the existence of passive mode-locking and autosoliton generation in the cavity of the laser.

A numerical model for multiwavelength actively mode-locked erbium-doped fiber lasers is proposed. Findings reveal that self-phase modulation (SPM) and cross-phase modulation (XPM) enhances gain competition suppression (GCS) and produces high-quality pulses in the large anomalous dispersion regime.

The inclusion of field ionization models in kinetic plasma simulations is desired in several applications. The ionization rates in these models are sensitive to noise in the electric field; however, and in some cases, spurious 'numerical' ionization may dominate the physical ionization. In this paper, analytic ionization rates are obtained as a function of the noise spectrum of the electric field. These expressions have applicability to several settings, including colored noise, as are obtained from digital filters. As such, they provide a means for quantitatively assessing the efficacy of candidate noise mitigation schemes, such as increasing the computational particle number, temporally averaging the electric field, or applying more sophisticated digital filtering techniques. Index Terms--Ionization, level-crossing statistics, particle-in-cell simulation, short-pulse lasers.

A theory for intersubband lasers, based on the solution of the Maxwell-semiconductor Bloch equations for the laser field and active medium is presented. The collision contributions are treated within the relaxation rate approximation, where the relaxation rates are determined by microscopic scattering calculations.

Relative intensity noise (RIN) characterization of triangular ring lasers, fabricated through a self-aligned dry etching process in InGaAsP-InP is presented. Two different classes of ring laser behaviors are identified, showing clear dependence of RIN enhancement on the backscattering strength.

The in-plane polarization anisotropy of gain in CS GaInAsP-InP Q-wires including band mixing effects that happen because of elastic strain relaxation and from 2-D confinement is studied. Strong strain relaxation causes in-plane polarization anisotropy to show complex, non-monotonic dependence on the wire width as per calculations obtained.

A tunable photonic crystal coupled-cavity laser diode based on InP was developed and the tuning characteristics were compared with results from a transfer matrix model. The simple model, promising in its output characteristics could be used for monolithic integration into highly integrated photonic circuits.

A set of dynamical equations for single mode erbium distributed feedback fiber lasers was obtained keeping in mind spatial hole burning and the nonuniform modefield distribution. The spatial distribution of the laser mode was found to play a significant part in determining the output characteristics of the laser.

An aluminosilicate neodymium-doped fiber laser tunable in the 0.9-Mum wavelength range was studied for spectroscopic and tuning characteristics. A W-type core refractive index profile facilitated operation on the 0.9- Mum three-level transition in neodymium-doped double-clad fiber laser.

The design and implementation of a three-mirror Nd:YVO4 solid-state laser with an optimized aspheric third mirror was done. The spatial-mode characteristics were studied and it was confirmed that enhanced spatial-mode selection and mode-shaping could be achieved.

The possibilities of Tm:KGdW as a tunable 2- Mum CW laser at room temperature is investigated. Comparisons are made of the doping levels, pump wavelengths and polarization configurations and the advantages of the monoclinic double tungstates over other Tm-hosts are shown.

Two parameters valuable for laser design and power scaling are obtained by studying the evolution of thermal lensing versus absorbed pump power. The experimental features are explained and quantum efficiency of the samples is inferred through an analytical model that is developed.

A comprehensive time-domain noise model for vertical-cavity surface-emitting lasers is presented. The model is based on a deterministic quasi-three-dimensional dynamic model that treats the carrier transport heat generation and dissipation, and optical fields in the device.

The chemical oxygen-iodine laser (COIL) with a new chemical method of atomic iodine production is investigated, wherein iodine atoms are formed in the COIL cavity by the fast chemical reaction of hydrogen iodide with chlorine atoms that are also produced chemically. The variation of the iodine concentration along the gas flow in the laser cavity was considered very small, indicating a low rate of iodine atom recombination.

A comprehensive description is given of the design of compact femtosecond solid-state lasers that are based on novel multipass cavity (MPC) configurations to extend the resonator length. To investigate the limits of compactness and energy scaling, two-mirror MPC geometries are examined.

The threshold current temperature characteristic of highly strained InGaAs-GaAs double-quantum-well vertical-cavity surface-emitting lasers (VCSELs) in relation to the gain-cavity detuning at room temperature at room temperature is presented and assessed. A conceptual model that relates the gain-cavity detuning at room temperature sensitivity of the active region performance, which qualitatively describes the threshold current-temperature characteristic typical of VCSELs is proposed.

Q-switched and CW passive mode locking in a laser-diode-pumped Nd:GdVO(sub 4) laser with a semiconductor saturable absorber mirror has been demonstrated. The repetition rate of the Q-switched envelope increased from 23.1 to 260 kHz as the pump power increased from 1.75 to 13.0 W. At a pump power of 13.7 W, the Q-switched mode locking changed to CW mode locking.

A study has been done to measure the thermal lens in an Nd:YAG rod to be reduced by more than an order of magnitude when cooled with liquid nitrogen. It has been shown that cryogenic cooling resulted to a considerably enlarged power range for stable laser oscillation.

An optoelectronic design has been presented that integrates vertical-cavity surface-emitting lasers (VCSELs), optical emission filters and PIN photodetectors through a modification to a typical VCSEL structure and system designs have simulated and compared. VCSELs operating at 773 NM with one bottom N-type interactive contact showed CW single-mode and multimedia operation and output powers over 0.6mW, which is sufficient for high-quality sensors.

Strong optical bistability in a widely tunable L-band erbium-doped fiber ring laser pumped by a 980-nm laser diode is demonstrated. This simple configured laser gives strong optical bistability with added advantages such as control of the opeartion wavelength that can cover from 1560 to 1584 nm.

An optical feedback device that allows adjustment of the characteristic timescales of oscillations is described. The device could be made to oscillate at gigahertz frequencies making it suitable for chaos communication systems.dbi

A prepulse-free Nd:glass PW laser system of 0.9-PW peak power is developed to heat a pre-imploded high-density plasma. Specifications of the PW laser have also been summarized.

Novel method for saturation factors of absorption under optical pumping in solid-state lasers depends on the pumping scheme. However, it is through lasing that the saturation effect is recovered.

A diamond window has been used to cool high power Nd:YV04 laser head. The lasing slab that is pumped through the transparent chemical vapor deposition (CVD) diamond window, removes the heat from the pumped region.

The stability of pulsed emission in self-mode locked quantum cascade (QC) lasers is demonstrated. The enhancement of intracavity second-harmonic generation (SHG) as a result of high peek power is also observed.

The dynamics of injection-locked vertical cavity surface-emitting lasers (VCSELs) is studied as a function of temperature of the slave device. To take advantage of the stable locking region, the VCSEL device should have a minimum carrier density of 40 K -50 K below room temperature.

The scanning voltage microscopy (SVM) results on actively driven buried heterostructure (BH) multiquantum-well (MQW) lasers that exhibit current blocking failure at current injection operation are reported. Application of the SVM method assists in diagnosing the origins of externally-observed active optoelectronic devices such as lasers, modulators, and detectors.

The results of a theoretical model that is built to describe the temperature-dependent lasing characteristics of InAs-InGaAs quantum-dot (QD) lasers operating at 1.3 mu m, are reported. An improved model that allows both free carriers and excitons in the dots is introduced to adequately describe the performance of the lasers.

CW performance of multiquantum-well (MQW) GaAs-AIGaAs lasers, operating near 850 nm at 300 K, is investigated as a function of the doping level in the p-cladding layer. The internal quantum yield is found to be close to unity and optical losses are as low as 1.36 1/cm at the highest level of doping.

The experimental observations of the current-induced polarization switching, in vertical-activity surface-emitting lasers, accompanied by a decrease of the total output power at the switching point, are reported. It is concluded that the experimentally observed polarization switching, is from the mode with higher unsaturated net gain to the mode with lower unsaturated net gain.

The optical properties of the laser-machined channel are affected by the residual ablated material remaining in the atmosphere of the channel during femtosecond-laser deep hole drilling. The interplay between hole drilling, beam propagation, and non-liner beam interactions are demonstrated.

The study presents a quantum theory for the noise of optical pulses in actively mode-locked lasers with phase modulation and/or group velocity dispersion. It is useful for understanding the noise of chirped optical pulses in mode-locked lasers and is relevant to semiconductor mode-locked lasers.

The behavior of a vertical-cavity surface-emitting lasers(VCSELs) having two transverse modes with parallel polarization, which interact with an externally injected CW optical field, is numerically analyzed. Different dynamics regimes were found, varying on the injection strength and frequency of the injected field.

Based on the spatially independent model and the numerical results algorithm, the behaviors of the transverse mode competition of vertical-cavity surface-emitting lasers (VCSELs) are investigated and analyzed. The results are helpful to design and control the transverse mode characteristics of the output optical power of a VCSEL.

A 2-kW-class chemical oxygen-iodine laser (COIL) using nitrogen buffer gas is developed and tested since industrial applications of COIL devices would require the use of nitrogen as the buffer gas. The laser, with a gain length of 11.7cms, is energized by a square pipe-array jet-type singlet oxygen generator (SPJSOG) and employs a nozzle bank with a designed Mach number of 2.5.

An experimental and theoretical investigation into the low-frequency intensity noise characteristics of erbium-doped distributed feedback (DFB) fiber lasers is presented. In order to predict the intensity noise generated in a linear fiber laser and explain the observed noise characteristics, an analytical model is used.

The extent of overtone small-signal gain data measured while operating a small-scale hydrogen-fluoride (HF) laser is compared with fundamental lasing output spectra and spontaneous overtone emission spectra. The data are consistent with an equilibrium rotational distribution discussing the results in terms of their applicability to the question of rotational nonequilibrium in continuous wave HF lasers.