Ultrafast third-order optical nonlinearities of vertically-aligned ZnO nanorods

Third-order optical nonlinearities in anatase and rutile TiO2 thin films

“…The values of β and n 2 of the rutile TiO 2 films were calculated to be − 2.6 × 10 − 10 m/W and −2.7 × 10 − 17 m 2 /W. The values of Reχ (3) and Imχ (3) of rutile TiO 2 films were calculated to be −3.6 × 10 − 11 esu and − 2.2 × 10 − 11 esu.…”

“…The values of Reχ (3) and Imχ (3) of anatase TiO 2 films were calculated to be −7.1 × 10 − 11 esu and −4.42 × 10 − 12 esu, respectively. shows curves of OA and CA Z-scan measurements for the rutile TiO 2 film.…”

“…Anatase and rutile TiO 2 films have been widely characterized for their potential applications in solar cells, self-cleaning coatings, photocatalysis. In fact, the nonlinear optical properties in TiO 2 films have been also studied and the values of χ (3) were reported to be 4.0 × 10 − 12 and 2.4 × 10 − 12 esu for rutile and anatase films by the third-harmonic generation method [6], respectively. The experimental results were found to be in excellent agreement with the calculated χ (3) by Lines' model [7].…”

“…Materials with large third-order nonlinear susceptibility χ (3) and ultrafast response have attracted much interest due to their potential applications for all-optical switching, light-controlled phase, refractive index modulation, and optical power limiting devices. During the past years, the metal/dielectric composite films were reported to have large third-order nonlinear susceptibilities due to the great enhancement of local field [1,2].…”

“…However, a drawback of this kind of films is the thermal damage and light loss induced by the large resonance absorption. Recently, as a candidate for nonlinear optical materials, metal oxide thin films have attracted growing interest due to the high optical nonlinearity, fast response time, and low absorption index [3][4][5].…”