Tunable Non-linear Refraction Properties and Ultrafast Excited State Dynamics of Dicyanomethylene Dihydrofuran Derivative

Abstract

The third order non-linear optical response of a dicyanomethylene dihydrofuran compound (DCDHF-2V) was investigated using a Z-scan technique in picosecond and nanosecond time regimes. The results show that DCDHF-2V has excellent excited state non-linear refraction properties on both time regimes, and the non-linear refraction index is also solvent-dependent in the nanosecond regime. The excited state relaxation dynamics of DCDHF-2V were demystified via femtosecond transient absorption spectroscopy. The TA spectra reveal that the solvent viscosities have a substantial impact on the excited state relaxation of DCDHF-2V. The exotic photophysical phenomena in DCDHF-2V reported herein can shed new light on future development of small organic non-linear optical materials with large non-linear coefficients and fast response.

Improving the photostability of fluorescent dyes by polymer nano‐insulating layer

“…In addition, PCL as donor group was bonded to fluorescein to lead the acromial absorption intensity of PP x F nanoparticles at 450 nm to be lower than that of fluorescein and UF nanoparticles (Figure 3(c)). [27][28][29][30] Moreover, the fluorescence intensity of PP 10k F nanoparticles was higher than that of UF nanoparticles (Figure 3(d)). This is due to inhibition of aggregation between molecules which was effectively performed by PCL 10k grafted on fluorescein.…”