Accession Number : ADA305361

Title :   Neutron Damage in Distributed Bragg Reflectors and Microcavity Lasers.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Suriano, Mark A.

PDF Url : ADA305361

Report Date : DEC 1995

Pagination or Media Count : 109

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 nm. 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 3.83x10(exp13) NEUTRONS/CM2 and 2.19x10(exp13)NEUTRONS/CM2 respectively utilizing a 1 MeV equivalent (Si) neutron fluence.

Descriptors :   *RADIATION DAMAGE, *GALLIUM ARSENIDE LASERS, MIRRORS, SUBSTRATES, REFLECTANCE, BAND SPECTRA, REFLECTORS, BRAGG ANGLE, NEUTRON IRRADIATION, LASER COMPONENTS.

Subject Categories : Lasers and Masers
      Radioactiv, Radioactive Wastes & Fission Prod

Distribution Statement : APPROVED FOR PUBLIC RELEASE