Non-coherent exciton migration in J-aggregates of the dye THIATS: exciton–exciton annihilation and fluorescence depolarization

Scheblykin, Ivan G.; Varnavsky, O.P.; Bataiev, M.; Sliusarenko, Oleksii; Auweraer, Mark Van der; Vitukhnovsky, A. G.

doi:10.1016/s0009-2614(98)01224-x

Cited by 51 publications

(59 citation statements)

References 23 publications

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“…The BChl building blocks form strongly excitonically coupled systems as in J-type aggregates. 9,10 The excitonic coupling gives rise to a strongly redshifted absorption spectrum and an extremely large exciton diffusion length. 11 For a long time it had not been possible to experimentally obtain a molecular structure of the BChl organization.…”

Section: ' Introductionmentioning

confidence: 99%

Organization of Bacteriochlorophylls in Individual Chlorosomes from Chlorobaculum tepidum Studied by 2-Dimensional Polarization Fluorescence Microscopy

et al. 2011

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Chlorosomes are the largest and most efficient natural light-harvesting systems and contain supramolecular assemblies of bacteriochlorophylls that are organized without proteins. Despite a recent structure determination for chlorosomes from Chlorobaculum tepidum (Ganapathy Proc. Natl. Acad. Sci. U.S.A. 2009, 106, 8525), the issue of a possible large structural disorder is still discussed controversially. We have studied individual chlorosomes prepared under very carefully controlled growth condition by a novel 2-dimensional polarization single molecule imaging technique giving polarization information for both fluorescence excitation and emission simultaneously. Contrary to the existing literature data, the polarization degree or modulation depth (M) for both excitation (absorption) and emission (fluorescence) showed extremely narrow distributions. The fluorescence was always highly polarized with M ≈ 0.77, independent of the excitation wavelength. Moreover, the fluorescence spectra of individual chlorosomes were identical within the error limits. These results lead us to conclude that all chlorosomes possess the same type of internal organization in terms of the arrangement of the bacteriochlorophyll c transition dipole moments and their total excitonic transition dipole possess a cylindrical symmetry in agreement with the previously suggested concentric multitubular chlorophyll aggregate organization (Ganapathy Proc. Natl. Acad. Sci. U.S.A. 2009, 106, 8525).

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Section: ' Introductionmentioning

confidence: 99%

Organization of Bacteriochlorophylls in Individual Chlorosomes from Chlorobaculum tepidum Studied by 2-Dimensional Polarization Fluorescence Microscopy

et al. 2011

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“…Exciton-exciton annihilation has been extensively studied in molecular crystals, 3-7 molecular aggregates, [8][9][10] biological systems ͑photosynthetic light harvesting antennae and separate light harvesting complexes͒, [11][12][13][14][15][16] and -conjugated polymers. [17][18][19][20][21][22][23] For pulse repetition rates exceeding 10 6 Hz, even moderate laser pulse fluence of 10 10 -10 11 photons/ cm 2 can already lead to accumulation of relatively long lived triplet states via intersystem crossing, as was demonstrated by picosecond time-resolved fluorescence studies of pigmentprotein complexes of a photosynthetic bacterium Rhodospirillum rubrum.…”

Section: Introductionmentioning

confidence: 99%

Ultrafast dynamics of singlet-singlet and singlet-triplet exciton annihilation in poly(3-2′-methoxy-5′octylphenyl)thiophene films

et al. 2007

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Singlet-singlet ͑S-S͒ and singlet-triplet ͑S-T͒ exciton annihilation was studied in poly͑3-2Ј-methoxy5Јoctylphenyl͒thiophene films. For the S-S exciton annihilation studies, transient absorption spectroscopy at excitation laser pulse fluences of 1.2ϫ 10 13 -4.4ϫ 10 14 photons/ cm 2 and 2.5 kHz pulse repetition rate was applied. The obtained kinetics demonstrate a typical nonexponential character with intensity-dependent amplitudes and lifetimes. In time-resolved fluorescence experiments, low excitation pulse fluences of 1.6 ϫ 10 9 -2.2ϫ 10 12 photons/ cm 2 at high repetition rates of 0.4, 0.8, 4, and 81 MHz lead to S-T exciton annihilation as a result of triplet exciton accumulation. S-T annihilation kinetics results in monoexponential decay of the fluorescence kinetics and manifests itself as a decrease of the singlet exciton lifetime. The calculated time-independent S-S and S-T exciton annihilation rates strongly support the conclusion that the processes are controlled by the interchain diffusion of singlet excitons. Despite the low efficiency of S-T annihilation compared to that of S-S annihilation, it has a substantial effect on the singlet exciton lifetime due to a relatively long triplet lifetime ͑60 s͒. Thus, even optical excitation with low fluence at high pulse repetition rate creates a significant concentration of triplet states that efficiently quenches singlet excitons.

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“…Mathematically this problem is very close to that of quenching of mobile excitons in spatial domains that has been extensively studied theoretically in 1970-s in application to the phenomenon of exciton-exciton annihilation observed in photosynthetic molecular aggregates and polymers. [34][35][36] When decreasing the size of crystals, at some point, depending on the trap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 11 concentration, each nano-crystal may contain no or only very few traps, as a result of the Poissonian statistics of trap distribution. At this point PL of a crystal has a "digital" behaviorno traps leads to high PL already at the earliest times (no curing needed) and one or more traps cause perfect quenching (because the charge diffusion length is limited by trapping; without traps, charges probe the whole volume of the small crystal).…”

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confidence: 99%

Enhanced Organo-Metal Halide Perovskite Photoluminescence from Nanosized Defect-Free Crystallites and Emitting Sites

Tian

Merdasa

Unger

et al. 2015

J. Phys. Chem. Lett.

170

215

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Photoluminescence (PL) of organo-metal halide perovskite semiconductors can be enhanced by several orders of magnitude by exposure to visible light. We applied PL microscopy and super-resolution optical imaging to investigate this phenomenon with spatial resolution better than 10 nm using films of CH3NH3PbI3 prepared by the equimolar solution-deposition method, resulting in crystals of different sizes. We found that PL of ∼100 nm crystals enhances much faster than that of larger, micrometer-sized ones. This crystal-size dependence of the photochemical light passivation of charge traps responsible for PL quenching allowed us to conclude that traps are present in the entire crystal volume rather than at the surface only. Because of this effect, "dark" micrometer-sized perovskite crystals can be converted into highly luminescent smaller ones just by mechanical grinding. Super-resolution optical imaging shows spatial inhomogeneity of the PL intensity within perovskite crystals and the existence of <100 nm-sized localized emitting sites. The possible origin of these sites is discussed.

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Non-coherent exciton migration in J-aggregates of the dye THIATS: exciton–exciton annihilation and fluorescence depolarization

Cited by 51 publications

References 23 publications

Organization of Bacteriochlorophylls in Individual Chlorosomes from Chlorobaculum tepidum Studied by 2-Dimensional Polarization Fluorescence Microscopy

Organization of Bacteriochlorophylls in Individual Chlorosomes from Chlorobaculum tepidum Studied by 2-Dimensional Polarization Fluorescence Microscopy

Ultrafast dynamics of singlet-singlet and singlet-triplet exciton annihilation in poly(3-2′-methoxy-5′octylphenyl)thiophene films

Enhanced Organo-Metal Halide Perovskite Photoluminescence from Nanosized Defect-Free Crystallites and Emitting Sites

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