Transient absorption

Transient absorption is a well-known and well-established measurement technique in the femtosecond domain, and was extended into the attosecond regime using high harmonic generation in 2010. Transient absorption measures the probe pulse spectrum transmitted through the sample as a function of pump-probe delay.

In transient absorption spectroscopy, there is no intrinsic need for the presence of a strong laser field and it relies on the detection of photons. Photons do not suffer from space-charge effects, are insensitive to stray electric or magnetic fields, and can be detected very efficiently, sensitively, and with high dynamic range using existing CCD technology.

More info on attosecond transient absorption:

[327] L. Gallmann, C. Cirelli and U. Keller
Download"Attosecond science: recent highlights and future trends" (PDF, 676 KB) – Invited Paper
Annual Review of Physical Chemistry, vol. 63, pp. 447-469, 2012

2011

We were the first to use attosecond pulse trains (APTs) and observed for the first time sub-femtosecond dynamics with attosecond transient absorption:

[309] M. Holler, F. Schapper, L. Gallmann, U. Keller
Download"Attosecond electron wave-packet interference observed by transient absorption" (PDF, 188 KB)
Phys. Rev. Lett., vol. 106, 123601, 2011

2013

Invited Paper on attosecond transient absorption spectroscopy (ATAS):

[352] L. Gallmann, J. Herrmann, R. Locher, M. Sabbar, A. Ludwig, M. Lucchini, U. Keller
Download"Resolving intra-atomic electron dynamics with attosecond transient absoprtion spectroscopy" (PDF, 313 KB) – Invited Paper
Molecular Physics, vol. 111, Nos. 14-15, 2243-2250, 2013

[359] J. Herrmann, M. Weger, R. Locher, M. Sabbar. P. Rivière, U. Saalmann, J.-M. Rost, L. Gallmann, U. Keller
Download"Virtual single-photon transition interrupted: Time-gated optical gain and loss" (PDF, 1011 KB)
Phys. Rev. A, vol. 88, 043843, 2013

[355] M. Lucchini, J. Herrmann, A. Ludwig, R. Locher, M. Sabbar, L. Gallmann, U. Keller
Download"Role of electron wavepacket interference in the optical response of helium atoms" (PDF, 1.8 MB)
New Journal of Physics, vol. 15, 103010, 2013

2015

Time zero calibration for attosecond transient absorption spectroscopy

[385] J. Herrmann, M. Lucchini, S. Chen, M. Wu, A. Ludwig, L. Kasmi, K. J. Schafer, L. Gallmann, M. B. Gaarde, U. Keller
Download"Multiphoton transitions for delay-zero calibration in attosecond spectroscopy" (PDF, 1.5 MB)
New Journal of Physics, vol. 17, 013007, 2015

2016

Laser field driven charge dynamics approaching the petahertz frequency regime: Attosecond dynamical Franz-Keldysh effect in polycrystalline diamond

News items with more explanations: http://www.ulp.ethz.ch/news/ulp-news/2016/08/eth-news-and-nccr-must-highlight.html

[412] M. Lucchini, S. A. Sato, A. Ludwig, J. Herrmann, M. Volkov, L. Kasmi, Y. Shinohara, K. Yabana, L. Gallmann, U. Keller
Download"Attosecond dynamical Franz-Keldysh effect in polycrystalline diamond" (PDF, 1.9 MB)
Science, vol. 353, Issue 6302, pp. 916-919, 2016