DOCSLIB.ORG

Femtosecond and Attosecond Spectroscopy in the XUV Regime Arvinder S

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Femtosecond and Attosecond Spectroscopy in the XUV Regime Arvinder S IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 18, NO. 1, JANUARY/FEBRUARY 2012 351 Femtosecond and Attosecond Spectroscopy in the XUV Regime Arvinder S. Sandhu and Xiao-Min Tong (Invited Paper) Abstract—Attosecond-duration, fully coherent, extreme- [7], [8]. Time-resolved experiments with these laser-generated ultraviolet (XUV) photon bursts obtained through laser XUV pulses provide new insights into the electronic processes high-harmonic generation have opened up new possibilities in the in atoms, molecules, and surfaces [1]–[6], [9]–[15]. study of atomic and molecular dynamics. We discuss experiments elucidating some of the interesting energy redistribution mecha- Strictly speaking, apart from attosecond XUV pulses, the im- nisms that follow the interaction of a high-energy photon with a plementation of ultrafast XUV spectroscopy also requires pre- molecule. The crucial role of synchronized, strong-field, near-IR cisely synchronized strong field IR laser pulses. In fact, many laser pulses in XUV pump–probe spectroscopy is highlighted. We new experimental possibilities have emerged from this marriage demonstrate that near-IR pulses can in fact be used to modify between conventional strong-field (IR) and weak-field (XUV) the atomic structure and control the electronic dynamics on attosecond timescales. Our measurements show that the Gouy spectroscopic techniques. We refer to this entire class of exper- phase slip in the interaction region plays a significant role in these iments as ultrafast XUV+IR spectroscopy. attosecond experiments. We perform precision measurement of In the framework of XUV+IR spectroscopy, we will focus interferences between strong field-induced Floquet channels to on the developments along two main directions. One is the extract the intensity and phase dependence of photoionization utilization of XUV pulses for initiation of ultrafast chemical dynamics. Applications of emerging table-top ultrafast XUV sources in the study of core electron dynamics are also discussed. dynamics through inner-valence/multielectron excitations. The resulting femtosecond electronic and nuclear processes in such Index Terms—Atomic physics, attosecond, femtosecond, experiments are probed using time-delayed IR pulses. The other extreme-ultraviolet (XUV) spectroscopy., high harmonics. direction represents the use of attosecond duration XUV pulse trains to study and control the transient, strong field induced modification of the electronic structure of atoms. In these ex- I. INTRODUCTION periments, the XUV and IR fields are simultaneously present LTRAFAST atomic and molecular science has undergone and their relative delay is precisely controlled on attosecond U quite a revolution in the last few years. One of the ma- timescale. jor changes has been brought about by the arrival of ultra- A brief outline of this paper is as follows. In section II, we fast table-top extreme-ultraviolet (XUV) sources in the form show that ultrashort XUV excitation is a precursor of novel of attosecond-duration, high-frequency, coherent light pulses. excited-state dynamics. The role of IR pulses in pump–probe The birth of a new subfield, being termed as “attosecond sci- measurement of XUV excited electronic and nuclear wavepack- ence,” has been made possible by advances in laser technology, ets is investigated in Section III. Experimental methods are dis- detection methods, and theoretical calculations [1]. The excite- cussed in Section IV. Section V and VI focus on the attosecond ment in this field arises from the possibility of observation and measurements of XUV+IR ionization dynamics. The signifi- control at the level of electrons [2]–[6], which typically undergo cance of the Gouy phase slip and advantages of spatial imaging dynamics on the timescale of few-hundred attoseconds. of focal volume are demonstrated. We use the Floquet formal- The phenomenon underlying ultrashort XUV pulses is the ism to interpret the behavior of atomic structures in strong fields. extreme nonlinear interaction of intense near-IR laser pulses We show that ion-yield oscillations encode the IR field strength (>1014 W·cm−2 ) with atoms, which leads to the generation of dependence of transition matrix elements. Finally, we discuss laser high harmonics extending up to hundreds of electronvolts the new experimental possibilities in study of multielectron and core-electron dynamics. Manuscript received December 27, 2010; revised March 8, 2011; accepted II. ULTRASHORT XUV PULSE-INITIATED DYNAMICS March 8, 2011. Date of publication May 19, 2011; date of current version January 31, 2012. This work was supported by the National Science Foundation Most physical and chemical phenomena occur through the under Grant PHY-0955274. photoexcitation and subsequent evolution of electronic and nu- A. S. Sandhu is with the Department of Physics and College of Optical clear wavepackets [16]. Ultrashort light pulses in the IR, visi- Sciences, University of Arizona, Tucson, AZ 85737 USA (e-mail: sandhu@ physics.arizona.edu). ble and UV have been extensively used to uncover the nature X.-M. Tong is with the Center for Computational Sciences, University of and dynamics of excited molecular states [17]. However, most Tsukuba, Ibaraki 305-8573, Japan (e-mail: [email protected]). time-resolved studies of wavepacket dynamics have been lim- Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. ited to low-lying excited states, only a few electronvolt above Digital Object Identifier 10.1109/JSTQE.2011.2136332 the ground state. In contrast, many common processes in nature 1077-260X/$26.00 © 2011 IEEE 352 IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 18, NO. 1, JANUARY/FEBRUARY 2012 Fig. 2. (a) Intense near-IR femtosecond laser pulse focused on rare gas atoms Fig. 1. Inner-shell photoionization and correlated two-electron shake-up pho- leads to XUV emission. (b) Spectral output is in the form of odd harmonics toionization (b) either case leads to formation of highly excited molecular ions extending to hundreds of electronvolts. (c) Generation mechanism is a three that undergo fast fragmentation along multiple pathways. step process involving tunneling, acceleration and recollision of electronic wavepacket with core (d) Laser driven recollision mechanism repeats every half-cycle leading to synchronized attosecond duration XUV bursts. (e.g., solar irradiation of atmospheric molecules) lead to forma- tion of excited molecules high above the ground state (>20 eV). ciently generated in the photon-energy regime of 10–100 eV [see Fig. 1(a) illustrates the XUV photon initiated inner-shell ion- Fig. 2 (b)]. This is highly appropriate for probing excited state ization (solid line) and two-electron shake-up processes (dotted dynamics as most molecules exhibit peak oscillator strengths line) in a diatomic molecule generically labeled as A2 .Theterm in this photon-energy regime [19]. Third, the three step mecha- “shake-up” here broadly refers to the electronic processes where nism [20], [21] [see Fig. 2(c)] ensures the phase coherence and excitation accompanies the ionization. As seen from Fig. 1, the perfect synchronization between XUV attosecond pulse trains XUV interaction forms highly excited molecules in the multiple (APTs) (or single attosecond pulses) [22]–[26] and the driv- continua above the single or even double ionization threshold. ing IR pulses. This intrinsic subcycle synchronization allows The energy relaxation dynamics of these states often involves XUV+IR pump–probe experiments that can time resolve what fragmentation along steep potential energy surfaces (PES) such happens in the attoseconds or first few femtoseconds of photon– as those depicted in Fig. 1(b). The evolution of such highly ex- molecule interaction. cited states presents an interesting realm that involves correlated As an opening example, we discuss the fragmentation dy- electronic and nuclear motion on ultrafast timescales. namicsofN2 molecule, which represents the first measurement However, the real-time dynamics of highly excited molecules of XUV pulse initiated femtosecond molecular dynamics [15]. have remained largely unexplored. Conventional synchrotrons In this experiment, XUV pulse is used to create a localized could not directly emphasize the “dynamics” due to the lack ionic wavepacket ∼40 eV above the ground state [see Figs. 1 of time resolution. Similarly, the multiphoton/strong-field ap- and 3(a)]. Using photofragment imaging technique discussed in proach with IR/visible pulses is inadequate, as it preferentially Section IV, we observed two main product channels. The inner- 2 2 2 3 targets the loosely bound electrons and cannot directly access valence (2σg 2σu ) ionized molecules fragment into N(2s 2p ) inner electrons. and N+ (2s2 2p2 ). More importantly, certain excited molecular +∗ + Fortunately, the table-top XUV pulses obtained through laser ions (N2 ) evolve into ground state N and an excited neutral high-harmonic generation (HHG) provide an excellent source atom that has loosely bound (n = 3) electron attached to it. The in terms of photon energy and time resolution required to probe second excitation and fragmentation path is shown as lower po- fast electron–electron and electron–ion dynamics. In Fig. 2, we tential energy curve in Fig. 3(a) and it represents an interesting have summarized the essential aspects of laser HHG. For a and unexplored relaxation channel. detailed discussion of this process the reader is referred to an Using a time-delayed
Load more

Recommended publications
  • Arxiv:1912.00017V1 [Physics.Atom-Ph] 29 Nov 2019
    Theoretical Atto-nano Physics Marcelo F. Ciappina1 and Maciej Lewenstein2, 3 1Institute of Physics of the ASCR, ELI-Beamlines, Na Slovance 2, 182 21 Prague, Czech Republic 2ICFO - Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona), Spain 3ICREA - Instituci´oCatalana de Recerca i Estudis Avan¸cats,Lluis Companys 23, 08010 Barcelona, Spain (Dated: December 3, 2019) Two emerging areas of research, attosecond and nanoscale physics, have recently started to merge. Attosecond physics deals with phenomena occurring when ultrashort laser pulses, with duration on the femto- and sub-femtosecond time scales, interact with atoms, molecules or solids. The laser- induced electron dynamics occurs natively on a timescale down to a few hundred or even tens of attoseconds (1 attosecond=1 as=10−18 s), which is of the order of the optical field cycle. For com- parison, the revolution of an electron on a 1s orbital of a hydrogen atom is ∼ 152 as. On the other hand, the second topic involves the manipulation and engineering of mesoscopic systems, such as solids, metals and dielectrics, with nanometric precision. Although nano-engineering is a vast and well-established research field on its own, the combination with intense laser physics is relatively recent. We present a comprehensive theoretical overview of the tools to tackle and understand the physics that takes place when short and intense laser pulses interact with nanosystems, such as metallic and dielectric nanostructures. In particular we elucidate how the spatially inhomogeneous laser induced fields at a nanometer scale modify the laser-driven electron dynamics.
    [Show full text]
  • Atomic Clocks, 14–19, 89–94 Attosecond Laser Pulses, 55–57
    Index high-order harmonic generation, A 258–261 in strong laser fields, 238–243 Atomic clocks, 14–19, 89–94 in weak field regime, 274-277 Attosecond laser pulses, 55–57 metal-ligand charge-transfer, 253–254 organic chemical conversion, C 249–251 pulse shaping, 269–274 CARS microscopy with ultrashort quantum ladder climbing, 285–287 pulses, 24–25 simple shaped pulses, 235–238 Chirped-pulse amplification, 54–55 Tannor-Kosloff-Rice scheme, phase preservation in, 54–5 232–235 Chirped pulses, 271, 274–277, 235–238 via many-parameter control in liquid Coherent control, 225–266, 267–304, phase, 252–255 atoms and dimers in gas phase, Coherent transients, 274–285 228–243 bond-selective photochemistry, 248–249 D closed-loop pulse shaping, 244–246 coherent coupling, 238–243 Dielectric breakdown, 305–329 molecular electronic states, in oxide thin films, 318 238–241 phenomenological model of, 316 atomic electronic states, retrieval of dielectric constant, 322 241–243 Difference frequency generation, 123 coherent transients, 274–285 Dynamics, 146–148, 150, 167–196, control of electron motion, 255–261 187–224 control of photo-isomerization, of electronic states, 146–148 254–255 of excitonic states, 150 control of two-photon transitions, hydrogen bond dynamics, 167–196 285-287 molecular dynamics, 187–196 332 Femtosecond Laser Spectroscopy Femtosecond optical frequency combs, E 1–8, 12–21, 55–57, 87–108, 109–112, 120–128 Exciton-vibration interaction, 153–158 absolute phase control of, 55–57 dynamic intensity borrowing, attosecond pulses, 55–57 156–158 carrier-envelope offset frequency, Franck-Condon type, 159 3, 121 Herzberg-Teller type, 159–160 carrier envelope phase, 2, 121 interactions, 14–19 mid-infrared, 19-21, 120–127 F molecular spectroscopy with, 12–14 Femtochemistry, 198, 226 optical frequency standards, 14–19 Femtosecond lasers, 1–27 optical atomic clocks, 14–19, external optical cavities, 21–25 89–94 high resolution spectroscopy with, Femtosecond photon echoes.
    [Show full text]
  • Attosecond Science on the East Coast
    Attosecond Science on the East Coast Luca Argenti, Zenghu Chang, Michael Chini, Madhab Neupane, Mihai Vaida, and Li Fang Department of Physics & CREOL University of Central Florida The steady progress experienced by extreme non-linear optics and pulsed laser technology during the last decade of the XX century led to a transformative backthrough: the generation, in 2001, of the first attosecond extreme ultraviolet pulse. This was a revolutionary achievement, as the attosecond is the natural timescale of electronic motion in matter. The advent of attosecond pulses, therefore, opened the way to the time-resolved study of correlated electron dynamics in atoms, molecules, surfaces, and solids, to the coherent control of charge-transfer processes in chemical reactions and in nano-devices as well as, possibly, to ultrafast processing of quantum information. Attosecond research has been in a state of tumultuous growth ever since, giving rise to countless high-profile publications, the formation of a large international research community, and the appearance of new leading research hubs across the world. The University of Central Florida is one of them, establishing itself as the center of excellence for attosecond science on the US East Coast. The UCF Physics Department and CREOL host six internationally recognized leaders in attosecond science, Zenghu Chang, Michael Chini, Luca Argenti, Madhab Neupane, Mihai Vaida, and Li Fang (listed in the order they joined UCF), covering virtually all branches of this discipline, with topics ranging from theoretical photoelectron spectroscopy, to high-harmonic generation in gases and solids, the transient-absorption study of molecular core-holes decay, the time and angularly-resolved photoemission from topological insulators, heterogeneous catalysis control, and ultrafast nanoplasma physics.
    [Show full text]
  • Generation of Attosecond Light Pulses from Gas and Solid State Media
    hv photonics Review Generation of Attosecond Light Pulses from Gas and Solid State Media Stefanos Chatziathanasiou 1, Subhendu Kahaly 2, Emmanouil Skantzakis 1, Giuseppe Sansone 2,3,4, Rodrigo Lopez-Martens 2,5, Stefan Haessler 5, Katalin Varju 2,6, George D. Tsakiris 7, Dimitris Charalambidis 1,2 and Paraskevas Tzallas 1,2,* 1 Foundation for Research and Technology—Hellas, Institute of Electronic Structure & Laser, PO Box 1527, GR71110 Heraklion (Crete), Greece; [email protected] (S.C.); [email protected] (E.S.); [email protected] (D.C.) 2 ELI-ALPS, ELI-Hu Kft., Dugonics ter 13, 6720 Szeged, Hungary; [email protected] (S.K.); [email protected] (G.S.); [email protected] (R.L.-M.); [email protected] (K.V.) 3 Physikalisches Institut der Albert-Ludwigs-Universität, Freiburg, Stefan-Meier-Str. 19, 79104 Freiburg, Germany 4 Dipartimento di Fisica Politecnico, Piazza Leonardo da Vinci 32, 20133 Milano, Italy 5 Laboratoire d’Optique Appliquée, ENSTA-ParisTech, Ecole Polytechnique, CNRS UMR 7639, Université Paris-Saclay, 91761 Palaiseau CEDEX, France; [email protected] 6 Department of Optics and Quantum Electronics, University of Szeged, Dóm tér 9., 6720 Szeged, Hungary 7 Max-Planck-Institut für Quantenoptik, D-85748 Garching, Germany; [email protected] * Correspondence: [email protected] Received: 25 February 2017; Accepted: 27 March 2017; Published: 31 March 2017 Abstract: Real-time observation of ultrafast dynamics in the microcosm is a fundamental approach for understanding the internal evolution of physical, chemical and biological systems. Tools for tracing such dynamics are flashes of light with duration comparable to or shorter than the characteristic evolution times of the system under investigation.
    [Show full text]
  • Attosecond Streaking Spectroscopy of Atoms and Solids
    U. Thumm et al., in: Fundamentals of photonics and physics, D. L. Andrew (ed.), Chapter 13 (Wiley, New York 2015) Chapter x Attosecond Physics: Attosecond Streaking Spectroscopy of Atoms and Solids Uwe Thumm1, Qing Liao1, Elisabeth M. Bothschafter2,3, Frederik Süßmann2, Matthias F. Kling2,3, and Reinhard Kienberger2,4 1 J.R. Macdonald Laboratory, Physics Department, Kansas-State University, Manhattan, KS66506, USA 2 Max-Planck Institut für Quantenoptik, 85748 Garching, Germany 3 Physik Department, Ludwig-Maximilians-Universität, 85748 Garching, Germany 4 Physik Department, Technische Universität München, 85748 Garching, Germany 1. Introduction Irradiation of atoms and surfaces with ultrashort pulses of electromagnetic radiation leads to photoelectron emission if the incident light pulse has a short enough wavelength or has sufficient intensity (or both)1,2. For pulse intensities sufficiently low to prevent multiphoton absorption, photoemission occurs provided that the photon energy is larger than the photoelectron’s binding energy prior to photoabsorption, ħ휔 > 퐼푃. Photoelectron emission from metal surfaces was first analyzed by Albert Einstein in terms of light quanta, which we now call photons, and is commonly known as the photoelectric effect3. Even though the photoelectric effect can be elegantly interpreted within the corpuscular description of light, it can be equally well described if the incident radiation is represented as a classical electromagnetic wave4,5. With the emergence of lasers able to generate very intense light, it was soon shown that at sufficiently high intensities (routinely provided by modern laser systems) the condition ħω < 퐼푃 no longer precludes photoemission. Instead, the absorption of two or more photons can lead to photoemission, where 6 a single photon would fail to provide the ionization energy Ip .
    [Show full text]
  • Attosecond Time-Resolved Photoelectron Holography
    ARTICLE DOI: 10.1038/s41467-018-05185-6 OPEN Attosecond time-resolved photoelectron holography G. Porat1,2, G. Alon2, S. Rozen2, O. Pedatzur2, M. Krüger 2, D. Azoury2, A. Natan 3, G. Orenstein2, B.D. Bruner2, M.J.J. Vrakking4 & N. Dudovich2 Ultrafast strong-field physics provides insight into quantum phenomena that evolve on an attosecond time scale, the most fundamental of which is quantum tunneling. The tunneling 1234567890():,; process initiates a range of strong field phenomena such as high harmonic generation (HHG), laser-induced electron diffraction, double ionization and photoelectron holography—all evolving during a fraction of the optical cycle. Here we apply attosecond photoelectron holography as a method to resolve the temporal properties of the tunneling process. Adding a weak second harmonic (SH) field to a strong fundamental laser field enables us to recon- struct the ionization times of photoelectrons that play a role in the formation of a photo- electron hologram with attosecond precision. We decouple the contributions of the two arms of the hologram and resolve the subtle differences in their ionization times, separated by only a few tens of attoseconds. 1 JILA, National Institute of Standards and Technology and University of Colorado-Boulder, Boulder, CO 80309-0440, USA. 2 Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel. 3 Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA. 4 Max-Born-Institut, Max Born Strasse 2A, Berlin 12489, Germany. These authors contributed equally: G. Porat, G. Alon. Correspondence and requests for materials should be addressed to N.D.
    [Show full text]
  • Attosecond Light Pulses and Attosecond Electron Dynamics Probed Using Angle-Resolved Photoelectron Spectroscopy
    Attosecond Light Pulses and Attosecond Electron Dynamics Probed using Angle-Resolved Photoelectron Spectroscopy Cong Chen B.S., Nanjing University, 2010 M.S., University of Colorado Boulder, 2013 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirement for the degree of Doctor of Philosophy Department of Physics 2017 This thesis entitled: Attosecond Light Pulses and Attosecond Electron Dynamics Probed using Angle-Resolved Photoelectron Spectroscopy written by Cong Chen has been approved for the Department of Physics Prof. Margaret M. Murnane Prof. Henry C. Kapteyn Date The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentioned discipline. iii Chen, Cong (Ph.D., Physics) Attosecond Light Pulses and Attosecond Electron Dynamics Probed using Angle-Resolved Photoelectron Spectroscopy Thesis directed by Prof. Margaret M. Murnane Recent advances in the generation and control of attosecond light pulses have opened up new opportunities for the real-time observation of sub-femtosecond (1 fs = 10-15 s) electron dynamics in gases and solids. Combining attosecond light pulses with angle-resolved photoelectron spectroscopy (atto-ARPES) provides a powerful new technique to study the influence of material band structure on attosecond electron dynamics in materials. Electron dynamics that are only now accessible include the lifetime of far-above-bandgap excited electronic states, as well as fundamental electron interactions such as scattering and screening. In addition, the same atto-ARPES technique can also be used to measure the temporal structure of complex coherent light fields.
    [Show full text]
  • Attosecond Physics at the Nanoscale
    Home Search Collections Journals About Contact us My IOPscience Attosecond physics at the nanoscale This content has been downloaded from IOPscience. Please scroll down to see the full text. 2017 Rep. Prog. Phys. 80 054401 (http://iopscience.iop.org/0034-4885/80/5/054401) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 130.183.90.175 This content was downloaded on 09/05/2017 at 14:52 Please note that terms and conditions apply. You may also be interested in: High energy photoelectron emission from gases using plasmonic enhanced near-fields M F Ciappina, T Shaaran, R Guichard et al. Advances in attosecond science Francesca Calegari, Giuseppe Sansone, Salvatore Stagira et al. Numerical simulation of attosecond nanoplasmonic streaking E Skopalová, D Y Lei, T Witting et al. The birth of attosecond physics and its coming of age Ferenc Krausz Isolated few-attosecond emission in a multi-cycle asymmetrically nonhomogeneous two-color laser field Chao Yu, Yunhui Wang, Xu Cao et al. Spatial shaping of intense femtosecond beams for the generation of high-energy attosecond pulses E Constant, A Dubrouil, O Hort et al. Attosecond imaging of XUV-induced atomic photoemission and Auger decay in strong laser fields S Zherebtsov, A Wirth, T Uphues et al. IOP Reports on Progress in Physics Reports on Progress in Physics Rep. Prog. Phys. Rep. Prog. Phys. 80 (2017) 054401 (50pp) https://doi.org/10.1088/1361-6633/aa574e 80 Report on Progress 2017 Attosecond physics at the nanoscale © 2017 IOP Publishing Ltd M F Ciappina1,2, J A Pérez-Hernández3, A S Landsman4, W A Okell1, RPPHAG S Zherebtsov1, B Förg1, J Schötz1, L Seiffert5, T Fennel5, T Shaaran6, T Zimmermann7,8, A Chacón9, R Guichard10, A Zaïr11, J W G Tisch11, 11 11 11 11 3 054401 J P Marangos , T Witting , A Braun , S A Maier , L Roso , M Krüger1,12,13, P Hommelhoff1,12,14, M F Kling1,15, F Krausz1,15 and M Lewenstein9,16 M F Ciappina et al 1 Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str.
    [Show full text]
  • Siunitx – a Comprehensive (Si) Units Package∗
    siunitx – A comprehensive (si) units package∗ Joseph Wright† Released 2021-09-22 Contents 1 Introduction 3 2 siunitx for the impatient 3 3 Using the siunitx package 4 3.1 Numbers . 4 3.2 Angles . 5 3.3 Units . 6 3.4 Complex numbers and quantities . 7 3.5 The unit macros . 8 3.6 Unit abbreviations . 10 3.7 Creating new macros . 14 3.8 Tabular material . 15 4 Package control options 17 4.1 The key–value control system . 17 4.2 Printing . 18 4.3 Parsing numbers . 20 4.4 Post-processing numbers . 22 4.5 Printing numbers . 25 4.6 Lists, products and ranges . 28 4.7 Complex numbers . 31 4.8 Angles . 32 4.9 Creating units . 34 4.10 Using units . 35 4.11 Quantities . 38 4.12 Tabular material . 39 4.13 Locale options . 49 4.14 Preamble-only options . 49 5 Upgrading from version 2 49 6 Unit changes made by BIPM 51 ∗This file describes v3.0.31, last revised 2021-09-22. †E-mail: [email protected] 1 7 Localisation 52 8 Compatibility with other packages 52 9 Hints for using siunitx 52 9.1 Adjusting \litre and \liter ........................ 52 9.2 Ensuring text or math output . 53 9.3 Expanding content in tables . 53 9.4 Using siunitx with datatool .......................... 54 9.5 Using units in section headings and bookmarks . 55 9.6 A left-aligned column visually centred under a heading . 56 9.7 Regression tables . 57 9.8 Maximising performance . 58 9.9 Special considerations for the \kWh unit .
    [Show full text]
  • Download 01 Introduction -The Nature of Science and Physics.Pdf
    CHAPTER 1 Introduction: The Nature of Science and Physics Figure 1.1 Galaxies are as immense as atoms are small. Yet the same laws of physics describe both, and all the rest of nature—an indication of the underlying unity in the universe. The laws of physics are surprisingly few in number, implying an underlying simplicity to nature’s apparent complexity. (credit: NASA, JPL-Caltech, P. Barmby, Harvard- Smithsonian Center for Astrophysics) Chapter Outline 1.1 Physics: An Introduction • Explain the difference between a principle and a law. • Explain the difference between a model and a theory. 1.2 Physical Quantities and Units • Perform unit conversions both in the SI and English units. • Explain the most common prefixes in the SI units and be able to write them in scientific notation. 1.3 Accuracy, Precision, and Significant Figures • Determine the appropriate number of significant figures in both addition and subtraction, as well as multiplication and division calculations. • Calculate the percent uncertainty of a measurement. 1.4 Approximation • Make reasonable approximations based on given data. INTRODUCTION TO SCIENCE AND THE REALM OF PHYSICS, PHYSICAL QUANTITIES, AND UNITS What is your first reaction when you hear the word “physics”? Did you imagine working through difficult equations or memorizing ormulasf that seem to have no real use in life outside the physics classroom? Many people come to the subject of physics with a bit of fear. But as you begin your exploration of this broad-ranging subject, you may soon come to realize that physics plays a much larger role in your life than you first thought, no matter oury life goals or career choice.
    [Show full text]
  • Attosecond Control of Ionization by Wave-Packet Interference
    PHYSICAL REVIEW LETTERS week ending PRL 99, 233001 (2007) 7 DECEMBER 2007 Attosecond Control of Ionization by Wave-Packet Interference P. Johnsson,1,* J. Mauritsson,1,2 T. Remetter,1 A. L’Huillier,1 and K. J. Schafer2 1Department of Physics, Lund University, P.O. Box 118, SE-221 00 Lund, Sweden 2Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803-4001, USA (Received 24 August 2007; published 7 December 2007) A train of attosecond pulses, synchronized to an infrared (IR) laser field, is used to create a series of electron wave packets (EWPs) that are below the ionization threshold in .helium. The ionization probability is found to strongly oscillate with the delay between the IR and attosecond fields twice per IR laser cycle. Calculations that reproduce the experimental results demonstrate that this ionization control results from interference between transiently bound EWPs created by different pulses in the train. In this way, we are able to observe, for the first time, attosecond wave-packet interference in a strongly driven atomic system. DOI: 10.1103/PhysRevLett.99.233001 PACS numbers: 32.80.Rm, 32.80.Qk, 42.65.Ky Attosecond pulses [1,2] can be used to initiate and probing quantum dynamics because it depends on the control electron dynamics on a sub-femtosecond time scale spatial and temporal behavior of the wave packets in the [3]. The first step in this process occurs when an atom confining potential. The modulation in the total amount of absorbs an ultraviolet photon leading to the formation of an population excited out of the ground state results from the attosecond electron wave packet (EWP).
    [Show full text]
  • Attosecond Spectroscopy of Liquid Water Rounding Gas Phase
    RESEARCH CHEMICAL PHYSICS quartz nozzle with an inner diameter of ~25 mm. Evaporation from the jet created the sur- Attosecond spectroscopy of liquid water rounding gas phase. An extreme ultraviolet (XUV) attosecond pulse train (APT), obtained Inga Jordan, Martin Huppert*, Dominik Rattenbacher†, Michael Peper, Denis Jelovina, Conaill Perry, through high-harmonic generation of a ~30-fs Aaron von Conta, Axel Schild, Hans Jakob Wörner‡ near-IR laser pulse in an argon gas cell, was focused onto the liquid microjet (spot size Electronic dynamics in liquids are of fundamental importance, but time-resolved experiments have so far ~50 mm) together with a strongly attenuated remained limited to the femtosecond time scale. We report the extension of attosecond spectroscopy to the replica of the IR laser pulse. This resulted in liquid phase. We measured time delays of 50 to 70 attoseconds between the photoemission from liquid water the detection of electrons from both phases and that from gaseous water at photon energies of 21.7 to 31.0 electron volts. These photoemission delays simultaneously. [See (31) for details of the can be decomposed into a photoionization delay sensitive to the local environment and a delay originating from experimental setup.] electron transport. In our experiments, the latter contribution is shown to be negligible. By referencing liquid The photoelectron signals from the liquid water to gaseous water, we isolated the effect of solvation on the attosecond photoionization dynamics of phase were shifted and broadened relative to water molecules. Our methods define an approach to separating bound and unbound electron dynamics from the gas-phase signals, which enabled their dis- the structural response of the solvent.
    [Show full text]