Introduction. Theory and experiment of high-order harmonic
generation in narrow and extended media.
I.1. High-order harmonic generation in isotropic medium:
three-step model and macroscopic consideration of frequency conversion. I.2.
Overview of the applications of long gaseous media for the HHG. References.
1. HHG in short-length plasmas.
1.1. Modern history and perspectives of harmonic generation
in narrow plasma plumes. 1.2. Spatial coherence measurements of non-resonant
and resonant high-order harmonics generated in narrow laser ablation plumes. 1.3.
Resonance processes in plasma plumes. 1.4. Peculiarities of the high-order
harmonics from different narrow plasmas generating at 1 kHz repetition rate. 1.5.
Concluding comments. References.
2. HHG in extended plasmas.
2.1. Advanced properties of extended plasmas for efficient
high-order harmonic generation. 2.2. Enhanced harmonic generation using
different second-harmonic sources for the two-color pump of extended
laser-produced plasmas. 2.3. Modification of modulated plasma plumes. 2.4.
Characterization of the high-order harmonics of 64 fs pulses generated in
extended plasma plumes. 2.5. Concluding comments. References.
3. Quasi-phase-matching of harmonics in laser-produced
plasmas.
3.1. Perforated target ablation for the formation of the
modulated plasma for quasi-phase-matched harmonic generation. 3.2.
Quasi-phase-matching of harmonics using the variable multi-jet plasmas. 3.3.
QPM-induced enhancement of HHG during two-color pump of multi-jet plasmas. 3.4.
Peculiarities of QPM harmonics using different targets and pump schemes. 3.5.
Influence of plasma jet sizes and pulse energies on the characteristics of QPM
harmonics. 3.6. Concluding comments. References.
4. Peculiarities of the HHG in the extended plasmas produced
on the surfaces of different materials.
4.1. Harmonic generation in the plasmas produced on the
5-mm-long crystal surfaces. 4.2. Application of the laser plasmas produced on
the extended surfaces of elemental semiconductors. 4.3. Application of carbon
cluster-contained extended plasmas for the high-order harmonic generation of
ultrashort pulses. 4.4. Morphology of laser-produced carbon nanoparticle
plasmas and high-order harmonic generation of ultrashort pulses in extended
clustered media. 4.5. Graphene-contained extended plasma: a medium for the
coherent extreme ultraviolet light generation. 4.6. Concluding comments. References.
5. New opportunities of extended plasma induced harmonic
generation.
5.1. Third and fourth harmonics generation in laser-induced
periodic plasmas. 5.2. Resonance-enhanced harmonics generated in nanoparticle
and monomer plasmas. 5.3. Electron density measurements in laser-produced
plasma using the nonlinear optical method. 5.4. Concluding comments. References.
6. Harmonic characterization using different HHG schemes.
6. 1. Characterization of the high-order harmonics generated
in the extended plasmas. 6.2. Low- and high-order harmonic generation in the
extended plasmas produced by laser ablation of zinc and manganese targets. 6.3
Application of double femtosecond pulses for plasma harmonic generation. 6.4.
Concluding comments. References.
Summary: achievements and perspectives.
Rashid A. Ganeev is an internationally recognized
expert in the field of High Harmonic Generation (HHG) in laser ablation plasmas.
In the present book, he specifically addresses the case of extended ablation
plasmas as nonlinear media for HHG. The book describes the different
experimental approaches, shows the advantages and limitations regarding HHG
efficiency and discusses the particular processes that take place at longer
interaction lengths, including propagation and quasi-phase matching effects.
Several schemes have been proposed such as exploitation of a resonance between
pump laser and driven matter, use of nano-molecules and metal clusters, use on
modulated extended plasmas and so on.
The structure of the book follows a logical presentation of first
providing an overview of HHG in short length ablation plasma plumes and
introducing in the following chapters the different experimental approaches
tested to generate longer plumes. The results presented are a recollection of
the author´s own contributions but there are also plenty of references to
publications by other actors in the field. The book shows the perspectives of
further development of HHG in extended plasma plumes. It also provides an
updated recollection of the subject of plasma harmonics, which will be useful
for students and scholars working in this highly multidisciplinary domain
encountering material science, nonlinear optics and laser spectroscopy. The
present book brings the new researcher at the very frontier of the physics of
the interaction between laser and extended plasma; it will serve to the expert
as an essential compass to follow a predetermined path.
This book offers a review of the use of
extended ablation plasmas as nonlinear media for HHG of high-order harmonic
generation (HHG). The book describes the different experimental
approaches, shows the advantages and limitations regarding HHG efficiency and
discusses the particular processes that take place at longer interaction
lengths, including propagation and quasi-phase matching effects. It
describes the most recent approaches to harmonic generation in the extreme
ultraviolet (XUV) range with the use of extended plasma plumes, and how these
differ from more commonly-used gas-jet sources. The main focus is on studies
using extended plasmas, but some new findings from HHG experiments in narrow
plasma plumes are also discussed. It also describes how quasi-phase-matching in
modulated plasmas, as demonstrated in recent studies, has revealed different
means of tuning enhanced harmonic groups in the XUV region.
After an introduction to the fundamental
theoretical and experimental aspects of HHG, a review of the most important
results of HHG in narrow plasmas is presented, including recent studies of
small-sized plasma plumes as emitters of high-order harmonics. In Chapter 2,
various findings in the application of extended plasmas for harmonic generation
are analyzed. One of the most important applications of extended plasmas, the
quasi-phase-matching of generated harmonics, is demonstrated in Chapter 3,
including various approaches to the modification of perforated plasma plumes.
Chapter 4 depicts the nonlinear optical features of extended plasmas produced
on the surfaces of different non-metal materials. Chapter 5 is dedicated
to the analysis of new opportunities for extended plasma induced HHG. The
advantages of the application of long plasma plumes for HHG, such as resonance
enhancement and double-pulse method, are discussed in Chapter 6. Finally, a
summary section brings together all of these findings and discuss the
perspectives of extended plasma formations for efficient HHG and nonlinear
optical plasma spectroscopy.
The book will be useful for students and
scholars working in this highly multidisciplinary domain involving material
science, nonlinear optics and laser spectroscopy. It brings the new researcher
to the very frontier of the physics of the interaction between laser and
extended plasma; for the expert it will serve as an essential guide and
indicate directions for future research.