Optical Limiting Processes in Derivatized Fullerenes and Porphyrins/Phthalocyanines

1997 ◽  
Vol 488 ◽  
Author(s):  
R. Kohlman ◽  
V. Klimov ◽  
X. Shi ◽  
M. Grigorova ◽  
B. R. Mattes ◽  
...  

AbstractWe review our results from spectral studies of the ultrafast excited-state absorption in fullerenes and derivatized fullerenes. These results allow determination of both the spectral response of reverse saturable absorption (RSA) nonlinearities such as optical limiting (OL) in fullerenes, and the dynamical response for different morphologies. We have investigated the effects of thin film and various sol-gel glass environments on the nanosecond OL and femtosecond dynamics of derivatized fullerenes. These data provide evidence of decay pathways which compete with the intersystem crossing to a triplet from the initial singlet states. With appropriate processing, however, the OL response of derivatized-fullerene sol-gel glasses can be enhanced to approach that of the same molecule in solution, while significantly enhancing the optical damage threshold. The optical limiting of these derivatized fullerenes is compared with that of various porphyrin and phthalocyanine molecules.

1994 ◽  
Vol 374 ◽  
Author(s):  
Marc Brunel ◽  
Michael Canva ◽  
Alain Brun ◽  
Frédéric Chaput ◽  
Laurent Malier ◽  
...  

AbstractAluminophthalocyanine and fullerene were trapped in solid transparent matrices using the sol-gel process. The covalent bonding to the matrix improved the chemical stability of the fullerene doped sample. Solid state optical limiting at 532 nm, mainly due to reverse saturable absorption processes, was observed with such samples. The non-linear transmission threshold was typically about 10 mJ/cm2 and an induced density of 1.6 was observed with three orders of magnitude greater illumination. Fluorescent decay measurements support the choice of a three energy level absorption model for the process, which allows indirect measurement of the excited-state absorption.


2000 ◽  
Vol 09 (03) ◽  
pp. 315-342 ◽  
Author(s):  
J. SCHELL ◽  
R. LÉVY ◽  
B. HÖNERLAGE

We study the limiting dynamics of C 60-doped porous sol-gel glasses by single- and double-pulse pump-probe experiments. We find that, contrary to crystalline films of C60, reverse saturable absorption (RSA) of these solid samples can be described by a 5-level model developed for C 60-solutions. We observe an ultrafast rise time, a large transmission-decrease at high fluence, a shortened singlet-state lifetime as compared to solutions, but nevertheless an important triplet yield. We explain differences with respect to solutions by the absence of stabilizing aromatic solvents and by the interaction of the amorphous environment with the molecules, broadening considerably the spectral features of RSA.


2003 ◽  
Vol 07 (06) ◽  
pp. 447-451 ◽  
Author(s):  
Shuang Zhang ◽  
Zhou Yang ◽  
Hongwei Liu ◽  
Fu Xi ◽  
Zhi-xin Guo ◽  
...  

The optical-limiting properties of several water-soluble phthalocyanine derivatives in aqueous solution were measured at 532 nm with 10 ns pulses. The excited state absorption cross-section σex of the derivatives were determined with the Z-scan technique. The results showed that the phthalocyanine derivatives are materials for reverse saturable absorption. It was noted that the optical limiting performance of the phthalocyanine derivatives in aqueous solutions can be controlled through the addition of alkalis. These phthalocyanine derivatives possess good solubility in water and optical limiting controllability, which give rise to their use for practical applications.


2004 ◽  
Vol 13 (01) ◽  
pp. 45-54 ◽  
Author(s):  
SHENG-LI GUO ◽  
BING GU ◽  
TAO ZHANG

We report on the measurement of the nonlinear optical absorption and refraction coefficients of C60-containing polyurethane–urea films on a nanosecond scale at a 532-nm wavelength, using the Z-scan technique. The optical limiting properties were also observed. The results show that the C60 polyurethane–urea is a kind of homogeneous material with a range of C60 content. With the difference in C60 content in polymers, the optical limiting properties are many and the required transmittance and transmitted energy can be altered depending on the C60 content in polymers. We suggest that the third-order nonlinearities and optical limiting behavior are consistent with excited-state absorption (reverse saturable absorption) as a mechanism.


1999 ◽  
Vol 597 ◽  
Author(s):  
A. Malko ◽  
S. Xu ◽  
H-L. Wang ◽  
R. Kohlman ◽  
L. Smilowitz ◽  
...  

AbstractWe present our recent advances toward the development of high-performance solid-state optical limiting devices using reverse saturable absorption (RSA) dyes doped into optical host materials. Femtosecond transient absorption spectroscopy was employed to determine both the spectral regions of strong RSA, and the singlet-triplet excited-state dynamics. The optical limiting in the visible spectrum in both metallo-phthalocyanines and metallo-porphyrins is due to a combination of singlet and triplet RSA. Optical limiting performance was studied for RSA dyes in dual tandem limiters (both in solution and solid-state). Our best results in the solid-state yielded an attenuation of 400x, and a damage threshold of up to several mJ at f/5 focusing. The optical limiting at f/5 is further enhanced, particularly in the solid-state, by self-defocusing thermal nonlinearities.


1997 ◽  
Vol 479 ◽  
Author(s):  
B. H. Cumpston ◽  
K. Mansour ◽  
A. A. Heikal ◽  
J. W. Perry

AbstractPhthalocyanines (PC's) containing heavy metal central atoms have recently been recognized as leading candidates for reverse saturable absorption and optical limiting (OL) applications in the visible spectrum. Strong triplet excited state absorption brought about by a large intersystem crossing rate is responsible for the excellent limiting performance of these molecules. Moreover, devices which maximize the excited state population along the light path will demonstrate maximum limiting efficiency. A non-homogeneous distribution of indium tetra(tert-butyl) phthalocyanine chloride (InC1PC) has been shown to be very effective in attenuating 532 nm nanosecond laser pulses. This was accomplished by approximating a hyperbolic distribution of chromophores using discrete elements of fixed dye concentration. Greater OL should be achieved by fabricating materials containing a continuous concentration gradient of chromophore. This paper focuses on issues concerning the preparation of solid polymeric materials that contain such a chromophore gradient. This design is achieved by diffusing chromophore-containing solutions into partially polymerized poly(methyl methacrylate) (PMMA).


1999 ◽  
Vol 597 ◽  
Author(s):  
C. W. Spangler ◽  
E. H. Elandaloussi ◽  
B. Ozer ◽  
K. Ashworth ◽  
L. Madrigal ◽  
...  

AbstractDuring the past five years there has been considerable progress in the design of organic materials for optical power limiting (OPL) applications. One of the more promising and widely studied material approaches involves reverse saturable absorption (RSA) from various excited states. We have recently been examining the efficacy of utilizing highly absorbing photogenerated charge states for RSA. Both polaronic radical cations and bipolaronic dications are possible candidates for this mode of optical limiting. Equally intriguing are new approaches to designing chromophores with large two-photon absorption (TPA) cross-sections. For some pulse durations the effective two-photon cross-section for bis-(diphenylamino)diphenylpolyenes, and dendrimers based on these repeat units, are extraordinaryly large, indicative of excited state absorption. In this presentation we will discuss the possibility of combining these two optical limiting mechanistic paradigms in single structures, which may then be considered as bimechanistic optical power limiters.


1996 ◽  
Author(s):  
Duncan W. McBranch ◽  
Victor I. Klimov ◽  
Laura B. Smilowitz ◽  
M. Grigorova ◽  
Jeanne M. Robinson ◽  
...  

2016 ◽  
Vol 18 (41) ◽  
pp. 28674-28687 ◽  
Author(s):  
Taotao Lu ◽  
Chengzhe Wang ◽  
Levi Lystrom ◽  
Chengkui Pei ◽  
Svetlana Kilina ◽  
...  

Extending the acetylide ligand π-conjugation diminishes the terminal substituent effect on the lowest excited states, but expands the triplet excited-state absorption to the near-IR region.


1996 ◽  
Vol 62 (3) ◽  
pp. 293-297 ◽  
Author(s):  
Rama Chari ◽  
S. R. Mishra ◽  
H. S. Rawat ◽  
S. M. Oak

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