13 Creation of Organic-Metal Hybridized Nanocrystals …
263
band around at 600–630 nm in wavelength). The baseline at above λ = 700 nm is
almost zero. This fact suggests the resulting PVA composites thin film is transparent
and highly optical quality with too much less scattering loss. On the other hand, one
can see evidently the broad and intensively LSPR peak of deposited Au NPs in the
extinction spectrum of hybridized PDA NCFs ((λ Au, LSPR = ca. 500–550 nm) as well
as EAP of PDA NCFs.
13.3.2 Pump-Probe Method to Measure Transient
Transmission Spectrum for Evaluation of Third-Order
NLO Properties
Third-order harmonic generation (THG) method [22] and Z-scan method [14, 18] are
conventional techniques to evaluate third-order NLO properties, i.e., χ
(3) (ω) value.
However, the measurements are usually performed discontinuously at a specified
wavelength. This is the drawback in these methods. In other words, it is so difficult
to measure the wavelength dispersion of χ
(3) (ω), which would surely bring about
the difficulty for discussion about the correlation between χ
(3) (ω) and nanostructure
in the present hybridized systems. Recently, the experimental combination of pumpprobe method and spectroscopic ellipsometry has been paid an attention, instead of
the previous methods [36–39]. Namely, the wavelength dispersion of real and imaginary parts of χ
(3) (ω) value is calculated from the difference in complex dielectric
function, which is evaluated from experimentally determined wavelength dispersion of complex refractive index and transient transmission spectrum in the present
measurement technique.
A pump-probe method was setup for the measurements of transient transmission
spectrum (Fig. 13.10). Photo-degradation of PVA composites thin films has been
checked from reproducibility of transient component.
13.3.3 Transient Transmission Spectra of PDA Nanocrystal
Fibers and Hybridized PDA Nanocrystal Fibers
The transient transmission spectra for PDA NCFs and hybridized PDA NCFs have
been measured successfully by using the pump-probe method as described in the
previous sub-section (Fig. 13.11). The χ
(3) (ω) value basically increases with the
intensity of transient component, (T + T )/T [36, 37].
The transient transmission peak appeared strongly at λ = 630–670 nm in any cases.
Especially, the overall spectral shape in PDA NCFs corresponded to the extinction
spectra (Fig. 13.9a). On the other hand, the value of (T + T )/T unexpectedly became
smaller than that of PDA NCFs, although the volume fraction of hybridized PDA
NCFs is unclear exactly and not the same as that of PDA NCFs in PVA composites
263
band around at 600–630 nm in wavelength). The baseline at above λ = 700 nm is
almost zero. This fact suggests the resulting PVA composites thin film is transparent
and highly optical quality with too much less scattering loss. On the other hand, one
can see evidently the broad and intensively LSPR peak of deposited Au NPs in the
extinction spectrum of hybridized PDA NCFs ((λ Au, LSPR = ca. 500–550 nm) as well
as EAP of PDA NCFs.
13.3.2 Pump-Probe Method to Measure Transient
Transmission Spectrum for Evaluation of Third-Order
NLO Properties
Third-order harmonic generation (THG) method [22] and Z-scan method [14, 18] are
conventional techniques to evaluate third-order NLO properties, i.e., χ
(3) (ω) value.
However, the measurements are usually performed discontinuously at a specified
wavelength. This is the drawback in these methods. In other words, it is so difficult
to measure the wavelength dispersion of χ
(3) (ω), which would surely bring about
the difficulty for discussion about the correlation between χ
(3) (ω) and nanostructure
in the present hybridized systems. Recently, the experimental combination of pumpprobe method and spectroscopic ellipsometry has been paid an attention, instead of
the previous methods [36–39]. Namely, the wavelength dispersion of real and imaginary parts of χ
(3) (ω) value is calculated from the difference in complex dielectric
function, which is evaluated from experimentally determined wavelength dispersion of complex refractive index and transient transmission spectrum in the present
measurement technique.
A pump-probe method was setup for the measurements of transient transmission
spectrum (Fig. 13.10). Photo-degradation of PVA composites thin films has been
checked from reproducibility of transient component.
13.3.3 Transient Transmission Spectra of PDA Nanocrystal
Fibers and Hybridized PDA Nanocrystal Fibers
The transient transmission spectra for PDA NCFs and hybridized PDA NCFs have
been measured successfully by using the pump-probe method as described in the
previous sub-section (Fig. 13.11). The χ
(3) (ω) value basically increases with the
intensity of transient component, (T + T )/T [36, 37].
The transient transmission peak appeared strongly at λ = 630–670 nm in any cases.
Especially, the overall spectral shape in PDA NCFs corresponded to the extinction
spectra (Fig. 13.9a). On the other hand, the value of (T + T )/T unexpectedly became
smaller than that of PDA NCFs, although the volume fraction of hybridized PDA
NCFs is unclear exactly and not the same as that of PDA NCFs in PVA composites