Forecasting two-photon absorption based on one-photon properties

1. 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

2. Outline • Motivation • Experiments • Calculations • Conclusions

3. Motivation: Why to predict? N N C l N H N N N H N C l N N N N N N N N H N H N H N N N N C N N H N C l C l N C N N H H N N C l C l N C N N C N N N N N Which one is better? Why?

4. Motivation: What can quantum chemistry do? m, Em, m 1, E1, 1 0, E0, 0 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

5. Experiments: Setup sample Laser system L2 Coherent VERDI 6 4W CW 532nm 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 CCD camera control and DAQ PC LabView Filter wheel Ref. detector Corre- lator OSA FROG L1 Pulse characterization LN CCD sample 300 600 1200 l/mm-1 F1 M1 Jobin Yvon Triax 550 Perkin-Elmer Lambda900 Spectrophotometer Perkin-Elmer LS 50B Luminescence Spectrometer

6. Experimental Results Frequency, cm-1 Frequency, cm-1 1 , M-1cm-1 s2, GM Frequency, cm-1 4104 14 3104 s2, GM , M-1cm-1 2104 3 1104 10 , M-1cm-1 s2, GM s2, GM 0 s2, GM , M-1cm-1 5 3.75104 , M-1cm-1 11 2.5104 s2, GM 5104 4104 5104 4104 1.25104 , M-1cm-1 s2, GM 3104 3.75104 3.75104 3104 0 Wavelength, nm 2104 2.5104 2.5104 2104 1.25104 1.25104 1104 1104 Wavelength, nm 0 0 0 0

7. Calculations: How to? 1 0 Second order perturbation theory: Local field factors: Lorentz Onsager Dipole moments: Solvatochromic shifts Linear absorption, fluorescence Molecule density Fluorescence anisotropy

8. Calculations: Results 300 2, GM 200 11 2 300 12 100 2, GM 3 5 1 4 7 6 8 200 9 0 10 11 2 0 100 200 300 12 100 14 2, GM 5 3 6 4 1 7 9 8 0 10 0 100 200 300 2, GM

9. 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