An improved time-domain traveling-wave model for vertical-cavity surface-emitting lasers

The use of the time-dependent transfer matrix and wide-angle beam propagation method is proposed to improve the computational speed and accuracy of a recently developed time-domain traveling-wave model of vertical-cavity surface-emitting lasers. With suitable utilization of the transfer matrix, significant reduction of the total execution time of the traveling-wave model can be obtained. In addition, the use of the wide-angle beam propagation method can minimize the calculation error of the traveling-wave model due to the diffraction of light from the small aperture of the laser cavity.published_or_final_versio

Tunable semiconductor ring laser with filtered optical feedback: Traveling wave description and experimental validation

We study experimentally and theoretically a semiconductor ring laser with four filtering channels providing filtered delayed optical feedback. To describe and analyze the wavelength selection and tuning in this device, we exploit the traveling-wave model determining the evolution of optical fields and carrier density along the ring cavity and filtering branches. The numerical results agree with the experimental observations: we can reproduce the wavelength tuning, the multiple wavelength emission, and the wavelength switching speed measured in these devices. The traveling-wave model allows us to study in detail the effect of the different laser parameters and can be useful for designing the future devices

Tunable semiconductor ring laser with filtered optical feedback: Traveling wave description and experimental validation

We study experimentally and theoretically a semiconductor ring laser with four filtering channels providing filtered delayed optical feedback. To describe and analyze the wavelength selection and tuning in this device, we exploit the traveling-wave model determining the evolution of optical fields and carrier density along the ring cavity and filtering branches. The numerical results agree with the experimental observations: we can reproduce the wavelength tuning, the multiple wavelength emission, and the wavelength switching speed measured in these devices. The traveling-wave model allows us to study in detail the effect of the different laser parameters and can be useful for designing the future devices

Traveling wave model of an AWG-based multiwavelength laser

This work presents a traveling wave model description of an arrayed waveguide grating (AWG) based multiwavelength laser. The purpose is to design a device with frequency spacing of 70 GHz between channels at 1550 nm central wavelength, aiming to dimension the required channel bandwidth to achieve a target side mode suppression ratio (SMSR) among longitudinal modes

Longtime behavior of the traveling-wave model for semiconductor lasers

The traveling-wave model is a popular tool for investigating longitudinal dynamical effects in semiconductor lasers, e.g., sensitivity to delayed optical feedback. This model consists of a hyperbolic linear system of partial differential equations (PDEs) with one spatial dimension which is nonlinearly coupled with a slow subsystem of ordinary differential equations (ODEs). Firstly, we prove the basic statements about the existence of solutions of the initial-boundary-value problem and their smooth dependence on initial values and parameters. Hence, the model constitutes a smooth infinite-dimensional dynamical system. Then, we exploit this fact and the particular slow-fast structure of the system to construct a low-dimensional attracting invariant manifold for certain parameter constellations. The flow on this invariant manifold is described by a system of ODEs which is accessible to classical bifurcation theory and numerical tools like, e.g., AUTO

Longitudinal modes of multisection ring and edge-emitting semiconductor lasers

We use the traveling wave model for simulating and analyzing nonlinear dynamics of multisection ring and edge-emitting semiconductor laser devices. We introduce the concept of instantaneous longitudinal optical modes and present an algorithm for their computation. A semiconductor ring laser was considered to illustrate the advantages of the mode analysis

Mode transitions in DBR semiconductor lasers: Experiments, mode analysis and simulations

The performance of a multisection DBR semiconductor laser emitting around 1060 nm is experimentally and theoretically investigated. Simulations and mode analysis of the traveling wave model including temperature induced changes of the refractive index explain experimentally observed nearly-periodic transitions between neighboring cavity mode determined continuous wave states with increasing injection current

Numerical bifurcation analysis of traveling wave model of multisection semiconductor lasers

Traveling wave equations are used to model the dynamics of multisection semiconductor lasers. To perform a bifurcation analysis of this system of 1-D partial differential equations its low dimensional approximations are constructed and considered. Along this paper this analysis is used for the extensive study of the pulsations in a three section distributed feedback laser. Namely, stability of pulsations, different bifurcation scenaria, tunability of the pulsation frequency and its locking by the frequency of electrical modulation are considered. All these pulsation qualities are highly important when applying lasers in optical communication systems