Modern Experimental Techniques
in Ultrafast Atomic and Molecular
Physics
P. Madhusudhan, Rituparna Das, Pranav Bharadwaj, Pooja Chandravanshi,
Swetapuspa Soumyashree, Vinitha Nimma, and Rajesh K. Kushawaha
Abstract Electron dynamics in atoms and molecules occur on attosecond (10
−18 s)
timescale while nuclear dynamics take picosecond (10
−12 s) to femtosecond (10
−15
s) duration. Science at these timescales is known as ultrafast science. The advent of
femtosecond laser and modern experimental techniques made it possible to chase
the nuclear and electron dynamics in atoms and molecules, resulting in an avenue
for controlling molecular reactions. A new nonlinear phenomenon involving the
interaction of intense laser light with atoms known as high harmonic generation has
been discovered, which has given birth to attosecond science. Attosecond light pulses
have allowed probing and controlling the electron dynamics on their natural time
scales in atomic and molecular systems. It is even possible to make molecular movies
using modern electron or ion imaging techniques in conjunction with femtosecond
and attosecond light pulses. Several experimental techniques have been developed
and used in ultrafast sciences in the last 2–3 decades which has facilitated the study
of ultrafast molecular reactions. In this chapter, a description of the key experimental
techniques of ultrafast science is presented.
1 Introduction
Following molecular reactions on their natural timescale has been of prime interest
to many chemists and physicists, as it will eventually allow them to control the reactions. The advent of femtosecond laser and the further development of various ions or
electrons imaging techniques and the pump-probe experimental scheme has made it
possible to chase the electron and nuclear dynamics in atomic and molecular systems
on their natural time scales and also control the chemical dynamics [1–5]. Experimentally, the quantum control of molecular dynamics [6] is not a straightforward
task and is still a topic of ongoing research. At the center of this research is lightP. Madhusudhan · R. Das · P. Bharadwaj · P. Chandravanshi · S. Soumyashree · V. Nimma ·
R. K. Kushawaha (B)
Physical Research Laboratory, Ahmedabad, India
e-mail: kushawaha@prl.res.in
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021
D. K. Singh et al. (eds.), Modern Techniques of Spectroscopy, Progress in Optical Science
and Photonics 13, https://doi.org/10.1007/978-981-33-6084-6_10
257
in Ultrafast Atomic and Molecular
Physics
P. Madhusudhan, Rituparna Das, Pranav Bharadwaj, Pooja Chandravanshi,
Swetapuspa Soumyashree, Vinitha Nimma, and Rajesh K. Kushawaha
Abstract Electron dynamics in atoms and molecules occur on attosecond (10
−18 s)
timescale while nuclear dynamics take picosecond (10
−12 s) to femtosecond (10
−15
s) duration. Science at these timescales is known as ultrafast science. The advent of
femtosecond laser and modern experimental techniques made it possible to chase
the nuclear and electron dynamics in atoms and molecules, resulting in an avenue
for controlling molecular reactions. A new nonlinear phenomenon involving the
interaction of intense laser light with atoms known as high harmonic generation has
been discovered, which has given birth to attosecond science. Attosecond light pulses
have allowed probing and controlling the electron dynamics on their natural time
scales in atomic and molecular systems. It is even possible to make molecular movies
using modern electron or ion imaging techniques in conjunction with femtosecond
and attosecond light pulses. Several experimental techniques have been developed
and used in ultrafast sciences in the last 2–3 decades which has facilitated the study
of ultrafast molecular reactions. In this chapter, a description of the key experimental
techniques of ultrafast science is presented.
1 Introduction
Following molecular reactions on their natural timescale has been of prime interest
to many chemists and physicists, as it will eventually allow them to control the reactions. The advent of femtosecond laser and the further development of various ions or
electrons imaging techniques and the pump-probe experimental scheme has made it
possible to chase the electron and nuclear dynamics in atomic and molecular systems
on their natural time scales and also control the chemical dynamics [1–5]. Experimentally, the quantum control of molecular dynamics [6] is not a straightforward
task and is still a topic of ongoing research. At the center of this research is lightP. Madhusudhan · R. Das · P. Bharadwaj · P. Chandravanshi · S. Soumyashree · V. Nimma ·
R. K. Kushawaha (B)
Physical Research Laboratory, Ahmedabad, India
e-mail: kushawaha@prl.res.in
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2021
D. K. Singh et al. (eds.), Modern Techniques of Spectroscopy, Progress in Optical Science
and Photonics 13, https://doi.org/10.1007/978-981-33-6084-6_10
257