William Angerer - Department of Physics and Astronomy - University ...

Chapter 3
Experimental Ultrafast Nonlinear Optical Spectroscopy
In this chapter we discuss the nonlinear optical spectroscopy experimental setup. A
further discussion of our spectra normalization and the effects of an ultrafast laser
pulse on our measured second-harmonic generation signals (see also section 2.4.2) is
given. In addition, the characteristics of the fundamental light generating source. the
Ti:AI 2 0 3 laser, are discussed at length.
3.1 Optical Setup
Fig. 3.1 displays a schematic of the nonlinear optical setup. This setup is somewhat
similar to the one used by M. S. Yeganeh and J. Qi [49, 41J, but with a different
fundamental light source. The fundamental light source with frequency ....: was a
Ti:AI 2 0 3 laser, the details of which will be more thoroughly discussed in section 3.3.
Briefly, the Ti:AI 2 0 3 laser produces ultrashort near IR laser pulses (",,700-1000 nm)
at rate of 76 MHz. The individual ultrashort pulses have sufficiently high peak powers
(",,50 kvV) to produce measurable nonlinear optical effects. Polarization of both
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