Third-order nonlinear optical properties of an ultrathin film containing a porphyrin derivative.
An ultrathin nanoscopic multilayer film has been fabricated through the electrostatic layer-by-layer self-assembly of negatively charged 5,10,15,20-tetrakis(3,4,5-trihydroxyphenyl)porphyrin (DHP) and oppositely charged polyethylenimine (PEI). UV-vis spectra showed a continuous and uniform deposition process of PEI and DHP. The film structure was characterized by small-angle X-ray diffraction measurement and AFM images. The nonlinear optical properties of ultrathin film were studied by Z-scan technique with laser duration of 8 ns at a wavelength of 532 nm. The film sample exhibited strong nonlinear saturated absorption and a self-defocusing effect. The nonlinear absorption coefficient and refractive index of the self-assembly ultrathin film are -9.7 x 10(-5) m/W and -7.56 x 10(-12) m(2)/W, respectively.
Jiang
Li
L
CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, P. R. China.
Lu
Fushen
F
Li
Hongmei
H
Chang
Qing
Q
Li
Yuliang
Y
Liu
Huibiao
H
Wang
Shu
S
Song
Yinglin
Y
Cui
Guanglei
G
Wang
Ning
N
He
Xiaorong
X
Zhu
Daoben
D