Detailed study of AlAs-oxidized apertures in VCSEL cavities for optimized modal performance

Abstract

Abstract-We present a numerical optical model for calculating threshold material gain in vertical-cavity surface-emitting lasers. It is based on a vectorial solution of Maxwell's equations and therefore gives exact results where other approaches fail, e.g., in the case of oxide-confined devices, which have high lateral index contrasts. Results are given concerning the influence of oxide window thickness and position on threshold gain and modal stability. We also propose an intuitive plane-wave model to enhance the physical understanding of these effects.

Comparison of optical VCSEL models on the simulation of oxide-confined devices

“…The starting point of our method is similar to the approach described in [13]: the VCSEL structure is placed in a perfect conducting cylindrical waveguide and the modes of that perfect conducting waveguide are used as an expansion basis. An orthonormal basis is calculated from this expansion basis using the modified Gram-Schmidt algorithm.…”

Efficient Computation of TM- and TE-Polarized Leaky Modes in Multilayered Circular Waveguides

“…Consider two waveguides with material parameters as provided in Table I. These structures correspond to the AlAsAlOx apertures in VCSEL cavities described in [13], [31]. For a free-space wavelength λ 0 = k 0 /2π = 1 µm, corresponding to an angular frequency of ω = 2π300 THz, the location of the TM-polarized propagation constants of a selected number of leaky modes are given in Figs.…”

Analysis of cylindrical waveguide discontinuities using vectorial eigenmodes and perfectly matched layers

“…2, both in the complex -plane and in the complex -plane. The parameters are chosen to correspond to the technologically important case of an aluminum-oxide (AlOx) aperture, where an isolating low-index AlOx ring inside a VCSEL resonator both acts as a focusing element and as a current confining structure [1]. The core has a radius m and consists of AlAs with refractive index .…”

“…The laser light exits the resonator perpendicular to the direction of the layers. These cavities can be considered as a sequence of cylindrical waveguides, each having a different thickness and cross section [1], [2].…”