Conical Intersection Dynamics in NO2 Probed by Homodyne High-harmonic Spectroscopy
Author: Hans Jakob Wörner
Publisher:
Published: 2011
Total Pages:
ISBN-13:
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Homodyne High-harmonic Spectroscopy
Author: Julien Beaudoin Bertrand
Publisher:
Published: 2012
Total Pages:
ISBN-13:
DOWNLOAD EBOOKAt the heart of high harmonic generation lies a combination of optical and collision physics entwined by a strong laser field. An electron, initially tunnel-ionized by the field, driven away then back in the continuum, finally recombines back to rest in its initial ground state via a radiative transition. The emitted attosecond (atto=10-̂18) XUV light pulse carries all the information (polarization, amplitude and phase) about the photorecombination continuum-to-ground transition dipolar field. Photorecombination is related to the time-reversed photoionization process. In this perspective, high-harmonic spectroscopy extends well-established photoelectron spectroscopy, based on charged particle detection, to a fully coherent one, based on light characterization. The main achievement presented in this thesis is to use high harmonic generation to probe femtosecond (femto=10-̂15) chemical dynamics for the first time. Thanks to the coherence imposed by the strong driving laser field, homodyne detection of attosecond pulses from excited molecules undergoing dynamics is achieved, the signal from unexcited molecules acting as the reference local oscillator. First, applying time-resolved high-harmonic spectroscopy to the photodissociation of a diatomic molecule, Br2 to Br + Br, allows us to follow the break of a chemical bond occurring in a few hundreds of femtoseconds. Second, extending it to a triatomic (NO2) lets us observe both the previously unseen (but predicted) early femtosecond conical intersection dynamics followed by the late picosecond statistical photodissociation taking place in the reaction NO2 to NO + O. Another important realization of this thesis is the development of a complementary technique to time-resolved high-harmonic spectroscopy called LAPIN, for Linked Attosecond Phase INterferometry. When combined together, time-resolved high-harmonic spectroscopy and LAPIN give access to the complex photorecombination dipole of aligned excited molecules. These achievements lay the basis for electron recollision tomographic imaging of a chemical reaction with unprecedented angstrom (1 angstrom= 0.1 nanometer) spatial resolution. Other contributions dedicated to the development of attosecond science and the generalization of high-harmonic spectroscopy as a novel, fully coherent molecular spectroscopy will also be presented in this thesis.
Resolving Strong Field Dynamics in Cation States of CO_2 via Optimised Molecular Alignment
Author: Malte Oppermann
Publisher: Springer Science & Business Media
Published: 2014-04-01
Total Pages: 218
ISBN-13: 3319053388
DOWNLOAD EBOOKThis thesis presents an experimental study of the ultrafast molecular dynamics of CO_2^+ that are induced by a strong, near-infrared, femtosecond laser pulse. In particular, typical strong field phenomena such as tunneling ionisation, nonsequential double ionisation and photo-induced dissociation are investigated and controlled by employing an experimental technique called impulsive molecular alignment. Here, a first laser pulse fixes the molecule in space, such that the molecular dynamics can be studied as a function of the molecular geometry with a second laser pulse. The experiments are placed within the context of the study and control of ultrafast molecular dynamics, where sub-femtosecond (10^-15 seconds) resolution in ever larger molecular systems represents the current frontier of research. The thesis presents the required background in strong field and molecular physics, femtosecond laser architecture and experimental techniques in a clear and accessible language that does not require any previous knowledge in these fields.
Fundamentals of Picoscience
Author: Klaus D. Sattler
Publisher: CRC Press
Published: 2013-09-26
Total Pages: 766
ISBN-13: 1466505095
DOWNLOAD EBOOKNow ubiquitous in public discussions about cutting-edge science and technology, nanoscience has generated many advances and inventions, from the development of new quantum mechanical methods to far-reaching applications in electronics and medical diagnostics. Ushering in the next technological era, Fundamentals of Picoscience focuses on the instrumentation and experiments emerging at the picometer scale. One picometer is the length of a trillionth of a meter. Compared to a human cell of typically ten microns, this is roughly ten million times smaller. In this state-of-the-art book, international scientists and researchers at the forefront of the field present the materials and methods used at the picoscale. They address the key challenges in developing new instrumentation and techniques to visualize and measure structures at this sub-nanometer level. With numerous figures, the book will help you: Understand how picoscience is an extension of nanoscience Determine which experimental technique to use in your research Connect basic studies to the development of next-generation picoelectronic devices The book covers various approaches for detecting, characterizing, and imaging at the picoscale. It then presents picoscale methods ranging from scanning tunneling microscopy (STM) to spectroscopic approaches at sub-nanometer spatial and energy resolutions. It also covers novel picoscale structures and picometer positioning systems. The book concludes with picoscale device applications, including single molecule electronics and optical computers. Introductions in each chapter explain basic concepts, define technical terms, and give context to the main material.
Attosecond and Strong-Field Physics
Author: C. D. Lin
Publisher: Cambridge University Press
Published: 2018-05-10
Total Pages: 419
ISBN-13: 1108187250
DOWNLOAD EBOOKProbing and controlling electrons and nuclei in matter at the attosecond timescale became possible with the generation of attosecond pulses by few-cycle intense lasers, and has revolutionized our understanding of atomic structure and molecular processes. This book provides an intuitive approach to this emerging field, utilizing simplified models to develop a clear understanding of how matter interacts with attosecond pulses of light. An introductory chapter outlines the structure of atoms and molecules and the properties of a focused laser beam. Detailed discussion of the fundamental theory of attosecond and strong-field physics follows, including the molecular tunnelling ionization model (MO-ADK theory), the quantitative rescattering (QRS) model, and the laser induced electronic diffraction (LIED) theory for probing the change of atomic configurations in a molecule. Highlighting the cutting-edge developments in attosecond and strong field physics, and identifying future opportunities and challenges, this self-contained text is invaluable for students and researchers in the field.
Time-Resolved Soft X-Ray Absorption Spectroscopy of Molecules in the Gas and Liquid Phases
Author: Cédric Schmidt
Publisher: Springer Nature
Published: 2021-03-19
Total Pages: 119
ISBN-13: 3030678385
DOWNLOAD EBOOKThis work studies the relaxation dynamics of molecules in both the gas and liquid phases after strong field ionization, using transient absorption in the soft X-rays. In particular, the thesis presents the first realization of time-resolved X-ray absorption spectroscopy in the spectral water window with a laser-based HHG source. These remarkable experiments were not only performed for isolated molecules, but also in liquids, for which the spectral coverage of the K-edges of C, N, and O are of primary importance for investigating biological molecules. The technique relies on the generation of high-order harmonics to further probe the electronic structure of molecules. Using the atomic selectivity of high energies and the temporal coherence of laser technology, we demonstrate the observation of the first stages of chemical transformation of matter in the gas and liquid phases.
Architecture and Design of Molecule Logic Gates and Atom Circuits
Author: Nicolas Lorente
Publisher: Springer Science & Business Media
Published: 2013-02-01
Total Pages: 284
ISBN-13: 3642331378
DOWNLOAD EBOOKHave you ever puzzled over how to perform Boolean logic at the atomic scale? Or wondered how you can carry out more general calculations in one single molecule or using a surface dangling bond atomic scale circuit? This volume gives you an update on the design of single molecule devices, such as recitfiers, switches and transistors, more advanced semi-classical and quantum boolean gates integrated in a single molecule or constructed atom by atom on a passivated semi-conductor surface and describes their interconnections with adapted nano-scale wiring. The main contributors to the field of single molecule logic gates and surface dangling bond atomic scale circuits theory and design, were brought together for the first time to contribute on topics such as molecule circuits, surface dangling bond circuits, quantum controlled logic gates and molecular qubits. Contributions in this volume originate from the Barcelona workshop of the AtMol conference series, held from January 12-13 2012.
Air Lasing
Author: Pavel Polynkin
Publisher: Springer
Published: 2017-12-16
Total Pages: 152
ISBN-13: 3319652206
DOWNLOAD EBOOKThis book presents the first comprehensive, interdisciplinary review of the rapidly developing field of air lasing. In most applications of lasers, such as cutting and engraving, the laser source is brought to the point of service where the laser beam is needed to perform its function. However, in some important applications such as remote atmospheric sensing, placing the laser at a convenient location is not an option. Current sensing schemes rely on the detection of weak backscattering of ground-based, forward-propagating optical probes, and possess limited sensitivity. The concept of air lasing (or atmospheric lasing) relies on the idea that the constituents of the air itself can be used as an active laser medium, creating a backward-propagating, impulsive, laser-like radiation emanating from a remote location in the atmosphere. This book provides important insights into the current state of development of air lasing and its applications.
Advances in Atomic, Molecular, and Optical Physics
Author: Susanne Yelin
Publisher: Academic Press
Published: 2020-06-17
Total Pages: 316
ISBN-13: 0128209887
DOWNLOAD EBOOKAdvances in Atomic, Molecular, and Optical Physics, Volume 69, the latest release in this ongoing series, provides a comprehensive compilation of recent developments in a field that is in a state of rapid growth, as new experimental and theoretical techniques are used on many problems, both old and new. Topics covered in this new release include Strong-field ion spectroscopy, Configurable microscopic optical potentials, Polaritons, Rydberg excitation of trapped cold ions - a new platform for quantum technologies, High intensity QED, Recollision imaging, and more. Presents the work of international experts in the field Contains comprehensive articles that compile recent developments in a field that is experiencing rapid growth, with new experimental and theoretical techniques emerging Ideal for users interested in optics, excitons, plasmas and thermodynamics Covers atmospheric science, astrophysics, and surface and laser physics, amongst other topics
Physical Chemistry of Cold Gas-Phase Functional Molecules and Clusters
Author: Takayuki Ebata
Publisher: Springer
Published: 2019-08-02
Total Pages: 395
ISBN-13: 9811393710
DOWNLOAD EBOOKThis book describes advanced research on the structures and photochemical properties of polyatomic molecules and molecular clusters having various functionalities under cold gas-phase conditions. Target molecules are crown ethers, polypeptides, large size protonated clusters, metal clusters, and other complex polyatomic molecules of special interest. A variety of advanced frequency and time-domain laser spectroscopic methods are applied. The book begins with the principle of an experimental setup for cold gas-phase molecules and various laser spectroscopic methods, followed by chapters on investigation of specific molecular systems. Through a molecular-level approach and analysis by quantum chemical calculation, it is possible to learn how atomic and molecular-level interactions (van der Waals, hydrogen-bonding, and others) control the specific properties of molecules and clusters. Those properties include molecular recognition, induced fitting, chirality, proton and hydrogen transfer, isomerization, and catalytic reaction. The information will be applicable to the design of new types of functional molecules and nanoparticles in the broad area that includes applied chemistry, drug delivery systems, and catalysts.
