Enhanced second-harmonic generation in Mg0.05Zn0.95O/Mg0.4Zn0.6O multilayers

Second-harmonic generation (SHG) from a Mg0.05Zn0.95O/Mg0.4Zn0.6O multilayers fabricated by the metalorganic chemical vapor deposition (MOCVD) technique was carried out. By comparing the second-harmonic signal generated in three kinds of sample, ZnO, Mg0.4Zn0.6O film and Mg0.05Zn0.95O/Mg0.4Zn0.6O multilayers, deposited at the same temperature and having almost the same thickness, we concluded that a significant enhancement of the second-harmonic signal can be achieved in Mg0.05Zn0.95O/Mg0.4Zn0.6O multilayers. The second-order susceptibility tensor χzzz(2)=21.2 pm/V was deduced from a multilayer structure deposited at 300 °C with a total thickness of ∼1 μm, which is about two times greater than that of ZnO and Mg0.4Zn0.6O films.