Ultralow-loss thin films have a very high prospect in applications such as frequency - stabilized lasers and optical atoms. GaAs/Al0.94Ga0.06 As distributed Bragg reflector(DBR) prepared by the metal organic vapor deposition (MOCVD). Systematically studied the GaAs/Al0.94Ga0.06As Bragg reflector scattering phenomenon and the absorption loss of DBR. The results show that the prepared DBR exhibits excellent surface morphology, RMS is about 0.2nm. The first order vector perturbation theory is used to analyze the scattering phenomenon of DBR. The ARS value of Bragg mirror is basically consistent with the experimental results under the full correlation theory, and the interface correlation coefficient is very close to 1. The total backscattering (TSb) of DBR was measured, and the results were less than 5ppm. At the same time, the absorption loss was studied, and a slightly higher absorption loss was detected, about 200ppm. Hall effect shows that the carrier concentration of DBR is as high as 1E18/cm3, and the free carrier absorption caused by P-type background doping is suspected to be the root cause of the excessive absorption.
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