title: Non-linear optical properties of zinc oxide nanowires.
abstract: High quality zinc oxide (ZnO) nanowires were grown on n-type Si (100) using vapor-liquid-solid process. We obtained the photoluminescence spectra of ZnO nanowires based on nonlinear optical process using an ultrashort wavelength femtosecond laser as a pumping source. The spectra shows the second harmonic generation phenomenon, as well as the exciton-exciton collision peak at 388 nm and the green emission peak at 515 nm caused by oxygen vacancy. A laser emission peak near 392 nm was observed when pump intensity surpassed 52 mJ/cm2 and a sharp peak about 0.5 nm wide emerged when the energy intensity reached 700 mJ/cm2. We attribute this excitation process to a two-photon absorption process enhanced by Rabi oscillation.
authors.affiliation: School of Microelectronics and Solid State Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China.
authors.forename: C F
authors.initials: CF
authors.lastname: Tang
authors.forename: H
authors.initials: H
authors.lastname: Deng
authors.forename: B
authors.initials: B
authors.lastname: Tang
authors.forename: H
authors.initials: H
authors.lastname: Cheng
authors.forename: J C
authors.initials: JC
authors.lastname: Wang
authors.forename: J J
authors.initials: JJ
authors.lastname: Chen