Neutron Damage in Distributed Bragg Reflectors and Microcavity Lasers

Author

Mark A. Suriano

Date of Award

12-1995

Document Type

Thesis

Degree Name

Master of Science

Department

Department of Engineering Physics

First Advisor

Paul H. Ostdiek, PhD

Abstract

Distributed Bragg Reflectors (DBRs) grown on a gallium-arsenide substrate for a solid state mirror and a vertical cavity surface emitting laser (VCSEL) were subjected to a neutron fluence to determine the sensitivity of the DBRs. The samples were irradiated at Ohio State University's 500 kW research reactor. Relative and absolute reflectance measurements were taken before and after each irradiation over a spectral band of 530 880 µm. Relative reflectance measurements showed that the irradiation did not cause any spectral shift over seven decades of neutron fluences. The reflectivity of the DBRs decreased from their initial measurements after being irradiated. The reflectance decrease was correlated to the incident neutron fluence to determine a Messenger Spratt type of equation to predict the DBRs response. A radiation damage constant for the VCSEL and DBR mirror were determined to be 3.83x10¹³ [neutrons/cm²] and 2.19x10¹³ [neutrons/cm²] respectively utilizing a 1 MeV equivalent (Si) neutron fluence.

AFIT Designator

AFIT-GA-ENP-95D-15

DTIC Accession Number

ADA305361

Recommended Citation

Suriano, Mark A., "Neutron Damage in Distributed Bragg Reflectors and Microcavity Lasers" (1995). Theses and Dissertations. 6117.
https://scholar.afit.edu/etd/6117