Phase-Locked Semiconductor Quantum Well Laser Arrays.
Abstract
This dissertation presents the experimental study of quantum well heterostructures in the III-V compound semiconductor system of (A1,Ga)As/GaAs. This study was conducted with a view to applying these structures in heterostructure lasers; specifically, phase-locked laser arrays. Broad area lasers fabricated from the quantum well microstructures exhibited threshold current densities as low as 200 Amp/sq. cm. The major contribution of this work is a new monolithic laser array structure which achieves phase-locking through coupling by diffraction in a central mode-mixing region where the light is unguided. The propagating eigen-modes are index-guided on either side of the mode-mixing region in parallel-element ridge waveguides. The new array displays narrow, single-lobe far-field patterns. The narrowest far-field pattern observed is 2 deg wide. An analytic model which explains the characteristics of the observed far-field patterns is presented. This model is developed from a premise with experimental basis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1987
- Accession Number
- ADA185155
Entities
People
- E. Towe
Organizations
- Massachusetts Institute of Technology