High-power single-mode vertical-cavity surface-emitting lasers via impurity induced disordering

Design principles of impurity-induced disordered (IID) vertical-cavity surface-emitting lasers (VCSELs) are presented, including the influence of IID on electrical, optical, and mode-control properties. A transfer matrix method (TMM) is developed to account for the diffusion of Group III atoms of the distributed Bragg reflectors (DBR) that comprise the VCSEL. In addition, a simple fiber model is used to design the transverse profile of the IID regions to maximize single-mode output power. IID VCSELs are fabricated with special attention given to the experimental parameters that affect both the lateral zinc diffusion profile and the level of intermixing caused by impurity diffusion. The resulting devices are compared to standard oxide-confined VCSELs and show lower operating voltage due to reduced contact and series resistance, higher operation ranges due to reduced thermal effects, and improved single-mode output due to the IID filter. Additionally, the optimal design for maximum single-mode output is experimentally determined by varying the dimensions of the IID aperture for a fixed oxide confinement size. Devices with an IID:Oxide ratio of 1.3:3 perform the best, yielding 1.6 mW of single-mode power and maintaining single-mode output for most of their operating range. Because of the discrepancy between the simple model’s prediction and the experimental results, a more complex mode-matching model is developed to capture the physics of the tapered IID aperture. Experimental control of the modeled optimal IID aperture is then investigated by sweeping the stress of the IID mask films. Finally, a single-interface mode-matching model is used to explore the viability of a metallic surface-relief VCSEL. This new mode-filtering mechanism would allow vertical integrability of multiple filtering mechanisms as well as alleviate current crowding issues often caused by surface etching and cavity damage.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Electrical & Computer Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2018

Author dc:creator

• O'Brien, Jr, Thomas R

Contributors dc:contributor

• Dallesasse, John M.
• Feng, Milton
• Nahrstedt, Klara
• Bayram, Can

• Vertical-cavity
• Surface-emitting
• Impurity-induced disordering
• Zn diffusion
• Single-mode

Statement dc:rights

• Copyright 2017 Thomas R O’Brien, Jr

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/99460

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/99460