Improvements for Generating High-Order Harmonics and Attosecond Pulses with Ultrashort Laser Fields
Thesis Defense
11:00 am –
1:00 pm
Jorgensen Hall Room: 207
Contact:
Physics Department, (402) 472-2770, paoffice@unl.edu
Dian Peng
Advisor: Anthony Starace and Ilya Fabrikant
ABSTRACT:
High-order harmonic generation (HHG) produced by ultrashort (few cycle) laser pulses possess interesting features which HHG produced by long pulses (many cycles) may not have. First, HHG spectra produced by ultrashort pulses can be extremely sensitive to the driving pulse waveform, which can be controlled by various laser parameters such as carrier-envelope phases (CEPs), time delays or frequency chirps. I will present strategies to enhance HHG by sculpting waveforms with chirp. Second, HHG spectra produced by ultrashort pulses exhibit large uneven peaks which are different from the usual odd high harmonics that long driving pulses produce. Based on this feature, I will present a solution for the attochirp problem in generating attosecond pulses.
Advisor: Anthony Starace and Ilya Fabrikant
ABSTRACT:
High-order harmonic generation (HHG) produced by ultrashort (few cycle) laser pulses possess interesting features which HHG produced by long pulses (many cycles) may not have. First, HHG spectra produced by ultrashort pulses can be extremely sensitive to the driving pulse waveform, which can be controlled by various laser parameters such as carrier-envelope phases (CEPs), time delays or frequency chirps. I will present strategies to enhance HHG by sculpting waveforms with chirp. Second, HHG spectra produced by ultrashort pulses exhibit large uneven peaks which are different from the usual odd high harmonics that long driving pulses produce. Based on this feature, I will present a solution for the attochirp problem in generating attosecond pulses.