Field Nonlinear Optics

In the absence of attosecond laser pulses, which could directly drive bound electron motion with attosecond precision— just as femtosecond pulses induce and drive femtosecond polarization in atoms, molecules and solids—ultrafast science relied upon the extreme nonlinearity of strong field ionization of matter in order to attain attosecond temporal resolution [1] and to capture electrons in motion [2].

I will discuss how recent advances in attosecond photonics permit the synthesis the control and the measurement of attosecond pulses at optical frequencies. These, nearly unidirectional electromagnetic fields of visible radiation combine the extreme field strength of modern lasers, the dramatic resolution and temporal confinement of extreme ultraviolet attosecond pulses [3] and the tunability of light transients [4],[5] in a single light tool that we name the attosecond light transient (ALT)[6].

I will show that, these precisely sculpted optical waves, can now offer new capabilities in controlling attosecond nonlinear dynamics of free and bound electrons in atoms and materials, beyond the strong field ionization regime, and thus enable the direct transfer of the techniques of nonlinear spectroscopy to the attosecond time domain, opening up the era of attosecond nonlinear optics.

References

[1]P.B Corkum and F. Krausz Nature Physics 3,381 (2007)
[2] E. Goulielmakis Nature 466, 793 (2010)
[3] E. Goulielmakis et al., Science 320, 1614 (2008).
[4] A. Wirth et al., Science 334,195 (2011).
[5] M. Th. Hassan et al., Rev. Sci. Instrum. 83,111301 (2012).
[6] Μ. Th. Hassan et al., to be submitted (2013)