1. Noisy Light Spectroscopy
Darin J. Ulness
Department of Chemistry
Concordia College, Moorhead, MN

2. Noisy Light Spectroscopy
What is noisy light?
History
Theory
Experiment
Applications and results
Context
The future of noisy light spectroscopy

3. What is Noisy Light? Time resolution on Broadband the order of the
correlation time, tc
Broadband
Phase incoherent
Quasi continuous wave
Noisy Light Spectrum
Frequency

4. What is Noisy Light? Ultrashort pulse Time resolution on
the order of the
pulse width
Broadband
Phase incoherent
Quasi continuous wave
Phase
locked
Coherent
Short Pulse Spectrum
Frequency
Time

5. What is Noisy Light? Phase Incoherent unlocked Time
Noisy Light Spectrum
Frequency
Time

6. Color locked! What is Noisy Light? Phase Incoherent unlocked Time
Noisy Light Spectrum
Frequency
Time

7. What is Noisy Light?
Beam B
Time

8. What is Noisy Light?
Beam B
Beam B’
Time

9. What is Noisy Light? t
Beam B
Beam B’
Time

10. What is Noisy Light? t
Compare t with tc
Beam B
Beam B’
Time

11. History FTC diagrams invented
Morita, Asaka, Hartmann develop the photon echo
Higher dimensional spectroscopy
Dugan develops Spectrally resolved CARS
Exciton quantum beats
1983
1986
1996
1998
2014
Most noisy light papers published between 1986 and Many counter parts to short pulse methods.
Noisy light focused on application of CARS. Very few groups working with noisy light from 1996 on.

12. Noisy Light Spectroscopy
Foundations of Noisy Light
Noisy Light Spectroscopy
Optical coherence theory
Perturbation theory: Density operator

13. P= c E Nonlinear Spectroscopy P(t) = P(1) + P(2) + P(3) …
Signal
Material
Light field
P= c E
Perturbation series approximation
P(t) = P(1) + P(2) + P(3) …
P(1) = c (1)E, P(2) = c (2)EE,
P(3) = c (3)EEE

14. CARS Coherent Anti-Stokes Raman Scattering wCARS -w2 w1-w2= wR w1
wCARS= w1 +wR
time

15. Bichromophoric Model
P(t)
(3) a
Noisy light
< >
P(s)
(3)* b

16. Theoretical Challenges
Complicated Mathematics
Complicated Physical Interpretation
Difficulty
The cw nature requires all field action permutations. The light is always on.
The proper treatment of the noise cross-correlates chromophores.

17. FTC Diagram Analysis Physics easy hard hard
Set of evaluated intensity level terms
Messy integration and algebra
Set of intensity level terms
(pre-evaluated)
Set of FTC diagrams
Construction
Rules
Evaluation
Rules
easy
hard
Physics
hard

18. a b FTC Diagram Analysis a b a b P(t,{ti}) P(s,{si}) P(t,{ti})
<BB’B’*B*> = <BB’*><B’B*> + <BB*><B’B’*>
time
time a b a b
P(t,{ti})
P(s,{si})
P(t,{ti})
P(s,{si})

19. FTC Diagram Analysis a b P(t,{ti}) P(s,{si})
arrow segments: t-dependent
correlation
line segments: t-independent
correlation

20. Indirect Correlation
time a b t t

21. Indirect Correlation
time a b t t
Dynamics on a are probed!

22. I(2)CARS: Experiment Signal is dispersed onto the CCD
Monochromator
Narrowband
Source
Broadband
Lens
Sample
Interferometer t B B’ M
I(2)CARS
Computer
CCD
Signal is dispersed onto the CCD
Entire Spectrum is taken at each delay
2D data set: the Spectrogram

23. I(2)CARS: Experiment
Great sensitivity to vibrational shifts and dephasing changes
Ring breathing mode of benzene in hexane

24. I(2)CARS: Data Processing
Fourier
Transformation
X-Marginal

25. I(2)CARS: Hydrogen Bonding
Neat
Pyridine FT
Pyridine/
Water
Xw= 0.55

26. I(2)CARS: Hydrogen Bonding

27. I(2)CARS: Hydrogen Bonding
Network model
Etc.
Thermalized distribution model
Fileti, E.E.; Countinho, K.; Malaspina, T.; Canuto, S.
Phys. Rev. E. 2003, 67,

28. Halogen Bonding Electropositve s-hole Electroneutral “ring”
Test Charge
Electroneutral
“ring”
Electronegative
“belt”

29. I(2)CARS: Halogen Bonding

30. Exciton Quantum Beats

31. Exciton Quantum Beats

32. Future of Noisy Light Spectroscopy Information Processing
I(4)2DES Theory
I(4)2DES Experiment
I(2)CARS Experiment
Information Processing
Dendritic Integration
Indirect correlation in systems
Applied Mathematics
Group Theory
Graph Theory
Braid Theory

33. Acknowledgements Students Funding Other Group Members Theory
Jahan Dawlaty
Dan Biebighauser
John Gregiore
Duffy Turner
Kurt Haag
Issac Heath
Carena Daniels
Method Development
Pye Phyo Aung
Tanner Schulz
Lindsay Weisel
Krista Cosert
Perrie Cole
Alex Harsh
Britt Berger
Zach Johnson
Thao Ta
Hydrogen/Halogen
bonding
Eric Berg
Jeff Eliason
Diane Moliva
Jason Olson
Scott Flancher
Danny Green
Exciton Beats
Erika Sutor
Becca Hendrickson
Meghan Knudtzon
Dylan Howie
Bobby Spoja
Funding
Other Group Members
NSF CAREER Grant CHE
Henry Dreyfus Teacher/Scholar program
Concordia Chemistry Research Fund
Dr. Mark Gealy, Department of Physics
Dr. Eric Booth, Post-doctoral researcher
Dr. Haiyan Fan, Post-doctoral researcher