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Development of a High-Sensitivity Pump-Probe Fast Scanning Delay Line. Stephanie Majewski University of Illinois @ Urbana-Champaign University of Florida Faculty Mentor: Professor David Reitze. Introduction. Femtosecond “LASER”s Pump-Probe Spectroscopy Lock-in Method Fast-Scan System.
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Development of a High-Sensitivity Pump-Probe Fast Scanning Delay Line Stephanie Majewski University of Illinois @ Urbana-Champaign University of Florida Faculty Mentor: Professor David Reitze
Introduction • Femtosecond “LASER”s • Pump-Probe Spectroscopy • Lock-in Method • Fast-Scan System
Femtosecond Lasers 1 fs = 0.000 000 000 000 001 s
What Happens in 100 Femtoseconds? • Light Travels 30 μm • Electrons Collide With Electrons • Solids Begin to Melt Under Laser Irradiation • Chemicals Dissociate There are about as many femtoseconds in a minute as there are minutes in the age of the universe.
Project Objectives • Characterize Motion of Shaker • Design Mirror Mount • Optimize Performance of Shaker- Mount System • Implement System in Pump-Probe Experiment
Obstacles ... • Elliptical Beam Shape • Unstable Mirror Mount • Wobble in Drive Arm of Shaker
Solutions! • Uniform Bolt Force on Mirror Yielded Circular Beam Shape, Mirror Rattle Minimized • Extra Screw Added Stability to Mount • Beam Jitter Corrected Optically
Time-Resolved Nanotube Transmission Measurement • Achieved successful fast-scan system implementation in pump-probe experiment • Measurement itself unsuccessful due to intrinsic scattering of sample • In future, can try using cross-polarization and other methods to reduce scattering.
Conclusion • Developed Shaker Design for Fast Scanning System • Characterized Shaker Motion and Corrected Beam Jitter to Within Acceptable Limits • Implemented Shaker in Time-Resolved Carbon Nanotube Transmission Measurement
Acknowledgements Professor David Reitze Mark Moores and Anatoly Efimov Drs. Kevin Ingersent and Alan Dorsey NSF Research Experience for Undergraduates