Forecasting twophoton absorption based on onephoton properties

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Forecasting two-photon absorption based on
one-photon properties
Nikolay Makarov, Department of Physics, Montana
State University
Mikhail Drobizhev, Zhiyong Suo, Aleks Rebane E.
Scott Tarter, Benjamin D. Reeves, Brenda
Spangler Fanqing Meng, Charles W. Spangler Craig
J. Wilson, Harry L. Anderson
Department of Physics, Montana State University,
Bozeman, MT Sensopath Technologies, Inc.,
Bozeman, MT MPA Technologies, Inc., Bozeman,
MT Department of Chemistry, University of Oxford,
Mansfield, Oxford, UK
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Outline

• Motivation
• Experiments
• Calculations
• Conclusions

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Motivation Why to predict?
Which one is better? Why?
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Motivation What can quantum chemistry do?
C. Katan, S. Tretiak, M.H.V. Werts, A.J. Bain,
R.J. Marsh, N. Leonczek, N. Nicolaou, E. Badaeva,
O. Mongin, M. Blanchard-Desce, Two-photon
transitions in quadrupolar and branched
chromophores experiment and theory, J. Phys.
Chem. B 2007, 111, 9468-9483
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Experiments Setup
sample
Laser system
Coherent VERDI 6 4W CW 532nm
L2
Coherent MIRA 900 0.5W 795nm 150fs
Wavelength control
Hamamatsu Streak Camera C5680
Intensity control
Coherent LEGEND Regen. Amplifier 1.1W 1kHz
795nm 150fs
USB Serial
TOPAS-C 0.3W 1kHz 125fs
Digital Oscilloscope Ref. Channel DAQ
GPIB
PC LabView
CCD camera control and DAQ
Filter wheel
Ref. detector
Corre- lator
OSA
FROG
L1
LN CCD
Pulse characterization
sample
300 600 1200 l/mm-1
F1
M1
Jobin Yvon Triax 550
Perkin-Elmer Lambda900 Spectrophotometer
Perkin-Elmer LS 50B Luminescence Spectrometer
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Experimental Results
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Calculations How to?
Second order perturbation theory
Local field factors
Lorentz
Onsager
Dipole moments
Solvatochromic shifts
Linear absorption, fluorescence
Molecule density
Fluorescence anisotropy
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Calculations Results
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Conclusions

• We show that the perturbation theory applied for
  two-level system quantitatively predicts the 2PA
  cross sections in dipolar molecules, provided
  that the necessary molecular parameters such as
  transition- and permanent dipole moments are
  independently measured.
• In most cases, the discrepancy between theory
  and experiment was less than 20, and always less
  than 50. This is the first time that such direct
  quantitative correspondence is demonstrated for a
  wide range of dipolar molecules.
• The overall significance of this work
  demonstrates a practical way how a set of
  relatively straightforward linear spectroscopic
  measurements can be used to study and predict
  nonlinear 2PA properties.

Acknowledgements
The work was supported by AFOSR.
See poster for details