Direct Observation of Highly Polarized Non-Linear Absorption Dipole of Single Semiconductor Quantum Rods

AbstractPolarization fluorescence microscopy was used to study the nature of the emission and nonlinear absorption dipole of single CdSe/ZnS quantum rods. Rods, with aspect ratios ranging from 2.75 to 15, showed strongly polarized emission consistent with previous one-photon studies. Non- linear excitation showed a sharp angular dependence fully consistent with the predicted two- photon absorption process. Two-photon absorption probes different transitions than linear absorption due to modified parity and angular momentum selection rules. The two-photon absorption dipole was found to be parallel to the emission polarization, and allows achieving highly orientation selective excitation of quantum rods. This is yet a further demonstration of single molecule measurements in unraveling basic principles of light-matter interaction that are otherwise masked by ensemble averaging.

Download Full-text

Novel s-tetrazine-based dyes with enhanced two-photon absorption cross-section

Journal of Materials Chemistry C ◽

10.1039/c5tc00531k ◽

2015 ◽

Vol 3 (32) ◽

pp. 8351-8357 ◽

Cited By ~ 14

Author(s):

Cassandre Quinton ◽

San-Hui Chi ◽

Cécile Dumas-Verdes ◽

Pierre Audebert ◽

Gilles Clavier ◽

...

Keyword(s):

Cross Section ◽

Absorption Cross Section ◽

Photon Absorption ◽

Absorption Cross ◽

Absorption Properties ◽

Linear Absorption ◽

Two Photon Absorption ◽

Two Photon ◽

Non Linear

This paper reports the synthesis and the linear and non-linear absorption properties of a series of new tetrazine-based D–π–A–π–D and D–π–A type dyes.

Download Full-text

Intrinsic five-photon non-linear absorption of two-dimensional BN and its conversion to two-photon absorption in the presence of photo-induced defects

Optical Materials ◽

10.1016/j.optmat.2018.10.022 ◽

2018 ◽

Vol 86 ◽

pp. 414-420 ◽

Cited By ~ 6

Author(s):

Yongchang Dong ◽

Prakash Parajuli ◽

Apparao M. Rao ◽

Wim Thielemans ◽

Samuel Eyley ◽

...

Keyword(s):

Photon Absorption ◽

Two Dimensional ◽

Linear Absorption ◽

Two Photon Absorption ◽

Two Photon ◽

Non Linear ◽

Induced Defects

Download Full-text

Synthesis of Functional Carbo-benzenes with Functional Properties: The C2 Tether Key

Synlett ◽

10.1055/s-0037-1610269 ◽

2018 ◽

Vol 30 (01) ◽

pp. 30-43 ◽

Cited By ~ 5

Author(s):

Valérie Maraval ◽

Remi Chauvin ◽

Kévin Cocq ◽

Cécile Barthes ◽

Arnaud Rives

Keyword(s):

Single Molecule ◽

Chemical Stability ◽

Charge Separation ◽

Electronic Structures ◽

Reduction Potential ◽

Photon Absorption ◽

Computational Results ◽

Two Photon Absorption ◽

Two Photon ◽

Prospects Of Application

Beyond demonstration of conceptual relevance and synthetic feasibility of aryl/alkyl-substituted representatives, carbo-benzene molecules started to gain prospects of broader impact through the emergence of alkynyl derivatives. This is first illustrated by examples of di- and hexaalkynyl-carbo-benzenes, a carbo-naphthalene, a carbo-biphenyl, and two carbo-terphenyls. A focus is then given to dialkynyl derivatives by reference to the peripherally C2-extruded parents. In the centrosymmetric quadrupolar series, the C2 expansion or ethynylogation effect is more particularly considered for 9H-fluoren-2-yl, tris(O-n-alkyl)pyrogallyl, indol-3-yl, 4-anilinyl, and tetraphenyl-carbo-phenyl substituents on the following respective properties: two-photon absorption, chemical stability, columnar mesogenicity, on-surface photoinduced charge separation vs single-molecule conductance, and reduction potential. Topical results and prospects of application are discussed on the basis of crystallographic, spectroscopic, and electrochemical analyses vs DFT-calculated nuclear and electronic structures. For the sake of the discussion consistency, complementary experimental and computational results are disclosed in the dianilinyl series. Overall, it is shown that combined advances in strategy, protocols, and substrate scope of acetylenic synthesis remain crucial for the development of yet poorly explored but promising types of molecular materials.1 Introduction2 Hexaalkynyl-carbo-benzene3 ortho-Dialkynyl-carbo-benzene4 para-Dialkynyl-carbo-benzenes4.1 Bistrimethylsilylethynyl-carbo-benzene4.2 Bisfluorenylethynyl-carbo-benzene4.3 Bistrialkoxyarylethynyl-carbo-benzenes4.4 Bisindolylethynyl-carbo-benzene4.5 Bisanilinylethynyl-carbo-benzene5 Carbo-oligo(phenyleneethynylene)s6 Conclusions

Download Full-text

Ultrafast sub–30-fs all-optical switching based on gallium phosphide

Science Advances ◽

10.1126/sciadv.aaw3262 ◽

2019 ◽

Vol 5 (6) ◽

pp. eaaw3262 ◽

Cited By ~ 10

Author(s):

Gustavo Grinblat ◽

Michael P. Nielsen ◽

Paul Dichtl ◽

Yi Li ◽

Rupert F. Oulton ◽

...

Keyword(s):

Gallium Phosphide ◽

Optical Switching ◽

Near Infrared ◽

Optical Nonlinearity ◽

Photon Absorption ◽

Linear Absorption ◽

Two Photon Absorption ◽

Two Photon ◽

All Optical ◽

All Optical Switching

Gallium phosphide (GaP) is one of the few available materials with strong optical nonlinearity and negligible losses in the visible (λ > 450 nm) and near-infrared regime. In this work, we demonstrate that a GaP film can generate sub–30-fs (full width at half maximum) transmission modulation of up to ~70% in the 600- to 1000-nm wavelength range. Nonlinear simulations using parameters measured by theZ-scan approach indicate that the transmission modulation arises from the optical Kerr effect and two-photon absorption. Because of the absence of linear absorption, no slower free-carrier contribution is detected. These findings place GaP as a promising ultrafast material for all-optical switching at modulation speeds of up to 20 THz.

Download Full-text

MULTIPHOTON EFFECTS IN THE POLYDIACETYLENE POLY BIS(P-TOLUENE SULFONATE) OF 2,4-HEXADIYNE-1,6-DIOL (PTS)

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863500000091 ◽

2000 ◽

Vol 09 (01) ◽

pp. 95-104 ◽

Cited By ~ 3

Author(s):

FUMIYO YOSHINO ◽

SERGEY POLYAKOV ◽

LARS FRIEDRICH ◽

MINGGUO LIU ◽

HOON SHIM ◽

...

Keyword(s):

Optical Quality ◽

Photon Absorption ◽

Multiphoton Absorption ◽

Linear Absorption ◽

High Optical Quality ◽

Two Photon Absorption ◽

Two Photon ◽

A Value ◽

Toluene Sulfonate ◽

Photon Spectra

Multiphoton absorption was investigated in single crystals of the polymer poly bis(p-toluene sulfonate) of 2,4-hexadiyne-1,6-diol (PTS). Using modified growth and polymerization techniques, high optical quality crystals were grown and their linear absorption spectrum measured. Very large four-photon absorption was measured using Z-scan with a value of α4=0.3 cm 5/ GW 3 obtained at 1600 nm. From the known one and two-photon absorption spectra, the three- and four-photon spectra are predicted to overlap. This leads to three-photon enhanced, four-photon absorption which is interpreted as the mechanism responsible for such large four-photon absorption.

Download Full-text

Preparation and Photophysical Properties of All-trans Acceptor–π-Donor (Acceptor) Compounds Possessing Obvious Solvatochromic Effects

Australian Journal of Chemistry ◽

10.1071/ch17021 ◽

2017 ◽

Vol 70 (9) ◽

pp. 1048

Author(s):

Yu-Lu Pan ◽

Zhi-Bin Cai ◽

Li Bai ◽

Sheng-Li Li ◽

Yu-Peng Tian

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Photophysical Properties ◽

Emission Spectra ◽

Photon Absorption ◽

Linear Absorption ◽

Functional Theory ◽

Two Photon Absorption ◽

Two Photon ◽

Donor Acceptor

A series of all-trans acceptor–π-donor (acceptor) compounds (BAQ, SFQ, BLQ, and XJQ) were conveniently synthesised and characterised by infrared, nuclear magnetic resonance, mass spectrometry, and elemental analysis. Their photophysical properties, including linear absorption, one-photon excited fluorescence, two-photon absorption, and two-photon excited fluorescence, were systematically investigated. All the compounds show obvious solvatochromic effects, such as significant bathochromic shifts of the emission spectra and larger Stokes shifts in more polar solvents. Under excitation from a femtosecond Ti : sapphire laser with a pulse width of 140 fs, they all exhibit strong two-photon excited fluorescence, and the two-photon absorption cross-sections in THF are 851 (BAQ), 216 (SFQ), 561 (BLQ), and 447 (XJQ) GM respectively. A combination of density functional theory (DFT) and time-dependent density functional theory (TDDFT) approaches was used to investigate the relationships between the structures and the photophysical properties of these compounds. The results show that they may have a potential application as polarity-sensitive two-photon fluorescent probes.

Download Full-text