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Ultrafast dynamics: new opportunities and challenges for Paris-Saclay Dynamique ultrarapide: enjeux et perspectives pour Paris-Saclay

Mercredi 11 février 2015, 9h-18h Auditorium de l'Institut d'Optique Graduate School

Avenue Augustin Fresnel, 91127 Palaiseau

Annonce finale / Final announcement

Pièce d'identité obligatoire / Mandatory ID card

Programme/program see p. 2

Abstracts : http://www.lumat.u-psud.fr/IMG/pdf/journee-opt2x_annonce.pdf

Inscription obligatoire / Free mandatory registration (see p.3)

Accès à l'IOGS / access to IOGS see p 4 or see the link https://www.institutoptique.fr/Institut/Plan-d-acces

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Programme / program

9h00 Accueil/registration

9h15 - 9h35 Danielle Dowek

ISMO LUMAT, Orsay Introduction - presentation of OPT2X

9h35 - 10h05 Dimitris Charalambidis

IESL-FORTH, Greece Non-linear processes in the XUV spectral region: An advanced tool for attosecond pulse metrology and application

10h05 - 10h35 Carlo Spezzani OPT2X, Orsay

Optical switch mediated by a magnetically active template studied with ultrafast XUV light sources

10h35 - 10h55 Pause Café / Coffee break

10h55 - 11h25 Françoise Remacle University of Liège

Dynamical Studies of Ultrafast Charge Migration in Diatomic and Modular Molecules Probed by Photoelectron Angular Distributions

11h25 - 11h45 Pascal Salières

LIDyL-LFP, Gif-sur-Yvette Attosecond spectroscopy in the gas phase: from charge migration to ionization delays

11h45 - 12h05 Olivier Guilbaud

LPGP, Orsay Coherent soft x-ray sources as a probe for dense plasma physics

12h05 - 12h35 Emma Springate

Rutherford Appleton Lab., UK

Time- and angle-resolved photoelectron spectroscopy in graphene with high harmonics

12h35 - 14h05 Lunch /poster session

14h05 - 14h35 Franck Delmotte IOGS, Palaiseau

XUV multilayer optics for ultrafast science

14h35 - 14h55 Guillaume Dovillaire Imagine Optic, Orsay

Adaptive optics on high power laser – EUV Wavefront measurement

14h55 - 15h15 Franck Lépine

ILM, Lyon Attosecond molecular physics, towards applications to complex molecules

15h15 - 15h35 Eric Constant

CELIA, Bordeaux Generation of High energy ultrashort XUV pulses for the study of non linear transitions induced by XUV photons

15h35 - 16h25 Table Ronde /Round table discussion

16h25 - 16h45 Pause café/Coffe break

16h45 - 17h15 Marta Fajardo

GoLP/IPFN, Portugal XUV High-Order Harmonic probing of XFEL created Warm Dense Matter

17h15 - 17h35 Rodrigo Lopez-Martens

LOA, Palaiseau Applications of attosecond lighthouses

17h35 - 17h55 Jan Luning

LCPMR, Paris Probing Ultrafast Magnetization Dynamics on the Nanometer Length Scale by Coherent X-ray Diffraction at XFELs

17h55 - 18h00 Conclusion

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Inscription / Registration

Un badge vous sera remis à l'accueil en échange d'une pièce d'identité.

An ID card is mandatory to receive the entrance badge

Merci d'avance pour votre compréhension et votre coopération !

En vue de faciliter l’accueil à l’IOGS et l’organisation de la journée, nous vous demandons de bien vouloir

remplir le questionnaire ci-dessous et le retourner le plus rapidement possible par mail à l'adresse suivante :

chantal.jucha@u-psud.fr

Nom/prénom :

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Présentation poster oui non

Titre du poster :

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1

Ultrafast dynamics: new opportunities and challenges for Paris-Saclay

Dynamique ultrarapide: enjeux et perspectives pour Paris-Saclay

Wednesday, February 11, 2015, 9 h - 18 h Auditorium of Institut d'Optique Graduate School

Avenue Augustin Fresnel, 91127 Palaiseau

Booklet of abstracts

OPT2X (Optimizing Optical pulses for XUV ultrafast science) is a LIDEX-2014 project funded by the Scientific Cooperation Foundation of Paris-Saclay. It aims at promoting innovative research in ultrafast dynamics, a rapidly growing field of interest for diluted and condensed matter physics as well as for plasmas. OPT2X relies on a unique potential of ultra-short intense XUV sources and original skills in XUV optics, implemented in several laboratories of the Paris-Saclay campus. This project gathers academic and industrial partners with the goal of developing specific instrumentation for the transport and control of light pulses. Users from several disciplines will therefore be able to conduct advanced research programs taking full advantage of the ultimate performance of the light sources (coherence, brightness, pulse duration from attoseconds to femtoseconds).

This first OPT2X scientific meeting addresses a large community of experimentalists and theoreticians, with the objective of stimulating scientific exchanges about new challenges in ultrafast dynamics. The presentations will inform on novel and even speculative trends in this field, including advanced instrumentation.

Partners of OPT2X LIDEX; Ultrafast XUV sources concerned by the first step of the project.

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Invited speakers

Dimitris Charalambidis IESL-FORTH, Greece

Non-linear processes in the XUV spectral region: An advanced tool for attosecond pulse metrology and applications

Eric Constant CELIA, Bordeaux

Generation of High energy ultrashort XUV pulses for the study of non linear transitions induced by XUV photons

Franck Delmotte IOGS, Palaiseau

XUV multilayer optics for ultrafast science

Guillaume Dovillaire Imagine Optic, Orsay

Adaptive optics on high power laser – EUV Wavefront measurement

Marta Fajardo GoLP/IPFN, Portugal

XUV High-Order Harmonic probing of XFEL created Warm Dense MatterErreur ! Source du renvoi introuvable.

Olivier Guilbaud LPGP, Orsay

Coherent soft x-ray sources as a probe for dense plasma physicsErreur ! Source du renvoi introuvable.

Franck Lépine ILM, Lyon

Attosecond molecular physics, towards applications to complex molecules

Rodrigo Lopez-Martens LOA, Palaiseau

Applications of attosecond lighthouses

Jan Luning LCP-MR, Paris

Probing Ultrafast Magnetization Dynamics on the Nanometer Length Scale by Coherent X-ray Diffraction at XFELs

Françoise Remacle University of Liège

Dynamical Studies of Ultrafast Charge Migration in Diatomic and Modular Molecules Probed by Photoelectron Angular Distributions

Pascal Salières LIDyL-LFP, Gif-sur-Yvette

Attosecond spectroscopy in the gas phase: from charge migration to ionization delays

Carlo Spezzani OPT2X, Orsay

Optically induced Fe magnetization reversal in Fe/MnAs/GaAs(001)

Emma Springate Rutherford Appleton Lab.,

UK

Time- and angle-resolved photoelectron spectroscopy in graphene with high harmonics

3

Non-linear processes in the XUV spectral region: An advanced tool for attosecond pulse metrology and applications

P.Tzallas1,6, E. Skatzakis1, P. A. Carpeggiani 1,2*, L. A. A. Nikolopoulos3, G. Tsakiris4 A. Palacios5, F. Martín5, D. Charalambidis1,2 ,6

1Foundation for Research and Technology - Hellas, Institute of Electronic Structure & Laser, PO Box 1527, GR71110

Heraklion (Crete), Greece 2Department of Physics, University of Crete, PO Box 2208, GR71003 Heraklion (Crete), Greece

3School of Physical Science, Dublin City University, Glasnevin, Dublin 9, Ireland

4Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching, Germany

5Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), Cantoblanco, 28049 Madrid,

Spain 6ELI Attosecond Light Pulse Source, ELI-Hu Kft., Dugonics ter 13, 6720 Szeged Hungary

* Current address: Dipartimento di Fisica, Politecnico di Milano E-mail: chara@iesl.forth.gr

In the last 12 years we have systematically developed the means for the generation of energetic XUV pulses with 1fs to sub-fs pulse duration, making use of the process of higher order harmonic generation (HOHG). Utilizing many cycle, high peak power driving laser pulses, in combination with the Interferometric Polarization Gating technique [1], XUV pulse intensities up to 1014W/cm2 have been reached in the spectral region 10-14eV. These pulses have been exploited in I) the temporal characterization of attosecond pulses [2],[3],[4]; II) the first proof of principle XUV-pump-XUV-probe experiments for the study of 1fs scale electron dynamics in atoms [5] as well as electronic, vibrational and ionization dynamics in molecules [6]. I will review these developments with emphasis to the XUV-pump-XUV-probe studies and address opportunities that are opening up in these and related scientific topics by the up-coming Extreme Light Infrastructure-Attosecond Light Pulse Source (ELI-ALPS), one of the three pillars of the ELI project of the European Forum on Research Infrastructures (ESFRI) roadmap.

[1] P. Tzallas et al. Nature Physics 3, 846 (2007) (doi: 10.1038/nphys747) [2] P. Tzallas et al. Nature 426, 267 (2003) (doi:10.1038/nature02091) [3] L. A. A. Nikolopoulos Phys. Rev. Lett.. 94, 113905 (2005) [4] Y. Nimura et al. Nature Physics 5, 124 - 128 (2009) [5] P. Tzallas et al. Nature Physics 7, 781 (2011) (DOI: 10.1038/NPHYS2033) [6] P. A. Carpeggiani, et al. Phys. Rev. A89, 023420 (2014) (doi:10.1103/PhysRevA.89.023420)

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Generation of High energy ultrashort XUV pulses for the study of non linear transitions induced by XUV photons

Eric Constant

Laboratoire CELIA, Université Bordeaux 1 351 Cours de la libération

33 405 Talence cedex, France

Attosecond pulses can now be generated (either isolated or as a train) and they are used to study ultrafast dynamics. Such dynamics are accessible by pump-probe experiments involving one attosecond pulse and a reference pulse that is often an intense IR pulse. As this probe field can perturb the system under study, it would be interesting to perform both the excitation and probe steps with XUV pulses in a perturbative way. This requires performing non-linear transitions induced by XUV photons which is possible with high energy XUV pulses and there is currently a large effort devoted to this goal.

During this talk, I will describe our approach for generating such high energy XUV pulses. This approach relies on using high energy fundamental pulses (TW femtosecond laser) that are spatially shaped to perform HHG in gases. Such spatial shaping allows us to perform HHG in a 1D configuration that reduces the impact of spatio temporal coupling that can otherwise strongly affect the XUV pulse and lead to non-homogeneous XUV beams.

5

XUV multilayer optics for ultrafast science

Franck Delmotte

Laboratoire Charles Fabry Institut d'Optique Graduate School

Campus Polytechnique - RD 128 2, avenue Augustin Fresnel

91127 PALAISEAU Cedex - France

One of the pioneers in coatings for optics in the extreme ultraviolet (EUV) spectral range (typically 10 to 60 nm), the "X-UV Optics" group of Laboratoire Charles Fabry study and optimize interferential mirrors based on multilayers for several applications since more than 30 years. Today, the main applications are related to the observation of the solar corona in astrophysics, optics for new x-ray sources (X-ray lasers, High Harmonics Generation Sources, Free Electron Lasers), optics for ultrashort pulses (attosecond science) or diagnostics of hot plasmas.

After a brief description of the theoretical principles of multilayer mirrors, we present the state of the art of experimental results obtained in the XUV range. We then focus on the specificities of multilayer mirrors for pico- and femto-second sources, in terms of reflectivity, selectivity and stability. Finally, we report the recent advances in the development of multilayer mirrors for attosecond sources.

6

Adaptive optics on high power laser – EUV Wavefront measurement

Guillaume Dovillaire

Technical Director Imagine Optic, 91400 Orsay France

High Harmonic Generation is a key technology to create short and intense XUV pulses. The infrared laser beam profile defines the main spatial characteristics of the XUV source. In order to control the spot size and reach diffraction limited performance, adaptive optics systems are used to compensate for the phase distortions created by the imperfect optical elements and thermal changes. We present the impact of common aberrations on the focal point, the existing technologies to measure the wavefront and to correct it. Adaptive optics architecture and algorithm are explained, some results and key figures presented.

Measuring the EUV beam wavefront is also very useful to understand the physics, to characterize the beam and to align focalization optics. The Hartmann technology is explained and some measurements showing that XUV diffraction limited beams are now feasible.

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XUV High-Order Harmonic probing of XFEL created Warm Dense Matter

G. O. Williams1, S. Kunzel1, S. Daboussi2, B. Iwan3, A. I. Gonzalez3, W. Boutu3, B. Barbrel3,V. Hilbert4,

U. Zastrau4, H. J. Lee5, B. Nagler5, E. Granados5, P. Heimann5, G. Dovillaire6, R. W. Lee7, J. Dunn,8 V. Recoules,9

C. Blancard9, P. Renaudin9, A. G. de la Varga1 0, P. Velarde1 0, H. Merdji3, Ph. Zeitoun2 and M. Fajardo 1

1 GoLP/Instituto de Plasmas e Fusão Nuclear-Laboratorio Associado, Instituto Superior Tecnico, Universidade de

Lisboa, 1049-001 Lisboa, Portugal 2 Laboratoire d'Optique Appliquée, ENSTA ParisTech CNRS, Ecole Polytechnique, UMR 7639, Chemin de la Hunière,

91761 Palaiseau, France 3 CEA/DSM/IRAMIS/LIDyL - 91191 Gif-sur-Yvette CEDEX - FRANCE

4 Institute of Optics and Quantum Electronics, Friedrich-Schiller University Jena, Max-Wien-Platz 1, 07743 Jena,

Germany 5 SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA

6 Imagine Optic, 18 Rue Charles de Gaulle, 91400 Orsay, France

7 Lawrence Berkeley National Laboratory, 1 Cyclotron Road, California 94720, USA

8 Lawrence Livermore National Laboratory, CA 94550, USA

9 CEA-DAM-DIF, Bruyeres Le Châtel, 91297 Arpajon Cedex, France

10 Instituto de Fusion Nuclear, Universidad Politcnica de Madrid, Jose Gutierrez Abascal 2, 28006 Madrid, Spain

The extreme ultra-violet (XUV) optical response of warm dense aluminium is a subject of much theoretical interest, yet lacking in experimental data. Recent experimental results pertaining to the optical properties of warm dense aluminium are reported. Thin foils of aluminium were heated with 60 fs pulses of x-rays above the aluminium k-edge at the LCLS. A probe pulse of XUV light from high harmonic generation (HHG) was used to measure optical properties during the transition from a cold solid, to the warm dense regime, and the plasma conditions were inferred from x-ray emission spectroscopy. The short pulse heating mechanism naturally separates the ion and electron temperatures in time, giving a unique insight into the contribution of each to the optical properties. An overall increase in absorption with increasing temperature was observed, coupled to a slightly decreased refraction measured with a wavefront sensor. While the final absorption and refraction values were in agreement with some Warm Dense Matter models, the dynamic response revealed the importance of ion heating timescales.

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Coherent soft x-ray sources as a probe for dense plasma physics

O.Guilbaud

LPGP, CNRS-Université Paris-Sud, campus d’Orsay, Orsay, France

Plasma-based soft x-ray lasers are intense coherent picoseconde sources of EUV radiation in the (10 - 40 nm) range which makes them valuable tools for dense plasma physics. After a general introduction, we will show in this presentation how the energy transport in a laser irradiated solid target can be probed with a soft x-ray laser. The different experiments presented here were performed with the LASERIX facility. This installation can generate perfectly timed soft x-ray lasers, high order harmonics and infrared pulses. A solid target was irradiated with a combination of high contrast infrared short pulses (35fs). The EUV transmission of the solid target under irradiation was measured for different delays with a Ni-like Ag soft x-ray laser emitting at 13.9nm. In order to track the heat penetration through the bulk material, targets are containing a thin layer of iron (50 nm) encased in plastic (CH). Heating of the iron layer gives rise to a rapid decrease in EUV opacity. Comparison of experimental results obtained in different configurations with hydro-codes simulations have been performed and the contributions of classical electron conduction, hot electron preheating and radiation transports have been deduced. We will conclude with the description of some prospects on XUV –XUV pump-probe experiments including a seeded laser source and transient grating technique.

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Attosecond molecular physics, towards applications to complex molecules

Franck Lépine

Institut Lumière Matière, Université Claude Bernard Lyon 1 Campus LyonTech- La Doua, Bâtiment Kastler,

10 rue Ada Byron 69622 Villeurbanne CEDEX, France

XUV attosecond pulses allow the investigation of charge dynamics in molecules. Such experiments can reveal quantum aspects of laser-molecule interaction such as electron correlation or non-adiabatic effects on the ultimate timescale. In this presentation we discuss results in which the combination of XUV and IR short pulses have been used to control and observe charge dynamics in increasingly complex molecular systems. Molecular reactivity driven by Sub-optical cycle dynamics, attosecond charge localization or hole dynamics are presented.

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Applications of attosecond lighthouses

Rodrigo Lopez-Martens

Laboratoire d’Optique Appliquée, Ecole Nationale Superieur de Techniques Avancées-Paristech, Ecole Polytechnique, CNRS UMR 7639, 91761 Palaiseau Cedex, France

In this talk, I will review the basic principles of ultrafast wavefront rotation of femtosecond laser pulses and its potential applications in attosecond science. Ultrafast wavefront rotation, or WFR, can be exploited to engineer new light sources for time-resolved studies, called ‘attosecond lighthouses’, to perform time-resolved measurements of nonlinear optical processes, using ‘photonic streaking’, or to track in-situ changes in the waveform of few-laser pulses during ultra-high intensity laser-matter interactions.

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Probing Ultrafast Magnetization Dynamics on the Nanometer Length Scale by Coherent X-ray Diffraction at XFELs

Coherent Diffraction Imaging of Ultrafast Magnetization Dynamics

Jan Lüning

Laboratoire de Chimie Physique – Matière et Rayonnement CNRS (UMR 7614), Université Pierre et Marie Curie, Paris, France

and Synchrotron SOLEIL, Gif-sur-Yvette, France

Since the discovery of the ultrafast demagnetization phenomenon by E. Beaurepaire and colleagues in 1996, the field of femtomagnetism has developed to an active research area. Initial experiments relied mostly on all-optical pump-probe techniques. Due to the rather long wavelength in the optical regime, however, no direct probing of the magnetization dynamics on the relevant nanometer length scales is possible. This limitation was overcome with the advent of X-ray free electron lasers emitting in the XUV and soft X-ray photon energy range. I will review in this talk our XFEL experiments relying on resonant magnetic X-ray scattering to combine femtosecond temporal with nanometer spatial resolution. By exploiting the XFEL's high degree of coherence, this has allowed us to obtain for the first time femtosecond time resolved images revealing the evolution of a nanometer-sized magnetic domain structure upon a localized excitation.

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Dynamical Studies of Ultrafast Charge Migration in Diatomic and Modular Molecules Probed by Photoelectron Angular Distributions

Françoise Remacle

Department of Chemistry, B6c, University of Liege, B4000 Liege, Belgium

The recent developments in the generation of optical attopulses suggest that it will soon become experimentally feasible to induce and subsequently directly probe ultrafast charge transfer between the end moieties of the modular molecule. One ultrafast pulse creates a non-stationary state of the neutral or of the cation and a second one ionizes it. Such experiments would allow characterizing a purely electronic time scale, before the coupling to the nuclei takes place. This is a pre Born-Oppenheimer regime where the electronic states are not stationary.[1]

We will report on the simulation of realistic pump probe experiments that monitor the ultrafast electronic dynamics in LiH,[2,3] in the medium size bifunctional molecule PENNA (C10H15N)[4] (Fig.1), C60 and other medium size molecules using a coupled equation scheme that includes the ionization continua and field effects. We show that in a short IR pump- XUV attosecond pulse train (APT) scheme that the APT can be used to disentangle the coherent superposition of states built by the IR pump pulse, acting as frequency filter.[2] The density motion between the two ends of a molecular system is probed by the anisotropy ionization parameter computed as the normalized difference between the ionization yields at the two moieties.[4] Heatmaps of the ionization anisotropy parameter as a function of the delay time between the two pulses and the kinetic energy of the photoelectron exhibit oscillations that reflect the beating periods of the electron density.

Schematic representation of the pump-probe experiments in (a) PENNA and in (b) LiH.

Acknowledgments: This work has the support of FRFC 2.4545.12 (FR and BM), of DoE AMOS DE-SC0012628 (FR-RDL) and of the Einstein Foundation (RDL)

References

[1] F. Remacle and R. D. Levine Proc. Natl. Acad. Sci. USA 2006, 103, 6793-6798. [2] B. Mignolet, R. D. Levine, F. Remacle Phys. Rev. A 2014, 88, 021403(R). [3] B. Mignolet, R. D. Levine and F. Remacle, J. Phys. Chem A 2014, 118 ,6721-6729. [4] B. Mignolet, R. D. Levine, F. Remacle J. Phys. B 2014, J. Phys. B: 47, 124011.

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Attosecond spectroscopy in the gas phase: from charge migration to ionization delays

Pascal Salières

Laboratoire Interaction, Dynamique, Laser (LIDyL) CEA Saclay, bat 522, 91191 Gif-sur-Yvette CEDEX - FRANCE

Attosecond pulses can be produced in the extreme ultraviolet (XUV) spectral range through the interaction of intense femtosecond infra-red laser pulses with atomic or molecular gases. They open the possibility of extending pump-probe spectroscopy from the femtosecond to the attosecond range. However, the extreme shortness of these pulses, together with the delicate XUV spectral range, impose severe constraints on the experimental arrangements for performing attosecond spectroscopy. I will discuss two examples of ultrafast studies: i) high harmonic spectroscopy, that may allow resolving charge migration in excited molecules or performing time-resolved quantum tomography of molecular orbitals; and ii) multi-color coherent photoionization, that gives access to tiny ionization delays such as the Wigner delays.

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Optically induced Fe magnetization reversal in Fe/MnAs/GaAs(001)

Carlo Spezzani

OPT2X (Optimizing Optical pulses for XUV ultrafast science)

The possibility to achieve the optical control of the local mangetization of given supporting media is of large interest to several communities because of its potential for applications in the development of future sensor and data storage technologies. The manipulation of the magnetic order can be driven or assisted by means of optical illumination with ultrashort laser pulses, the underlying mechanism being strongly depends on the material properties.

I will present and discuss the results of a time-resolved resonant scattering study exploring the magnetic and structural properties of the Fe/MnAs/GaAs(001) system.

We used a 100 fs optical laser pulse to trigger local temperature variations across the magneto-structural phase transition that takes place in the MnAs thin film in the 10 - 40 C range, and 100 fs soft x-ray free-electron laser pulses from the FERMI@Elettra FEL_1 light source to probe the induced magnetic and structural dynamics. The experiment provides direct evidence that a single optical laser pulse can reverse the Fe overlayer magnetization locally. The interpretation of the experimental data is supported by model calculations and it reveals that the magnetization reversal dynamics can be driven only by the self- organized coexistence of the two phases in the MnAs template that, in the present case, is occurring only during the slow regain of the system of its thermal equilibrium.

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Time- and angle-resolved photoelectron spectroscopy in graphene with high harmonics

Pr Emma Springate,

Central Laser Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire, OX11 0QX, UK

Graphene has great potential for use in optoelectronic or electronic applications, but exploiting its novel properties requires understanding of ultrafast electron dynamics in response to incident light. Time- and angle-resolved photoemission spectroscopy (tr-ARPES) is a powerful technique for directly observing electron dynamics in condensed matter. However, observing the electrons at the Dirac points in graphene requires a photon energy of >16 eV.

We have used tr-ARPES with 20-30 eV high harmonics to carry out the first direct measurements of electron dynamics in graphene, with sub-30 fs time-resolution. We have been able to observe a transient population inversion in graphene with a terahertz band-gap. Our measurements of electron lifetimes in the conduction band of bilayer graphene show that, in contrast to the monolayer, it has a band-gap that could make it suitable for electronics. We have also observed carrier multiplication, a potentially in