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Absolute timing of the photoelectric effect

Nature volume 561, pages 374–377 (2018)Cite this article

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Abstract

Photoemission spectroscopy is central to understanding the inner workings of condensed matter, from simple metals and semiconductors to complex materials such as Mott insulators and superconductors1. Most state-of-the-art knowledge about such solids stems from spectroscopic investigations, and use of subfemtosecond light pulses can provide a time-domain perspective. For example, attosecond (10−18 seconds) metrology allows electron wave packet creation, transport and scattering to be followed on atomic length scales and on attosecond timescales2,3,4,5,6,7. However, previous studies could not disclose the duration of these processes, because the arrival time of the photons was not known with attosecond precision. Here we show that this main source of ambiguity can be overcome by introducing the atomic chronoscope method, which references all measured timings to the moment of light-pulse arrival and therefore provides absolute timing of the processes under scrutiny. Our proof-of-principle experiment reveals that photoemission from the tungsten conduction band can proceed faster than previously anticipated. By contrast, the duration of electron emanation from core states is correctly described by semiclassical modelling. These findings highlight the necessity of treating the origin, initial excitation and transport of electrons in advanced modelling of the attosecond response of solids, and our absolute data provide a benchmark. Starting from a robustly characterized surface, we then extend attosecond spectroscopy towards isolating the emission properties of atomic adsorbates on surfaces and demonstrate that these act as photoemitters with instantaneous response. We also find that the tungsten core-electron timing remains unchanged by the adsorption of less than one monolayer of dielectric atoms, providing a starting point for the exploration of excitation and charge migration in technologically and biologically relevant adsorbate systems.

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Fig. 1: The atomic chronoscope method.
Fig. 2: Absolute timing of W(110) photoemission at 105 eV photon energy.
Fig. 3: Timing of adsorbate photoemission.

Data availability

The data that support the findings of this study are available from the corresponding authors upon request.

References

  1. Damascelli, A. Probing the electronic structure of complex systems by ARPES. Phys. Scr. T 109, 61–62 (2004).

    Google Scholar 

  2. Cavalieri, A. L. et al. Attosecond spectroscopy in condensed matter. Nature 449, 1029–1032 (2007).

    CAS  Google Scholar 

  3. Neppl, S. et al. Direct observation of electron propagation and dielectric screening on the atomic length scale. Nature 517, 342–346 (2015).

    CAS  Google Scholar 

  4. Seiffert, L. et al. Attosecond chronoscopy of electron scattering in dielectric nanoparticles. Nat. Phys. 13, 766–770 (2017).

    CAS  Google Scholar 

  5. Siek, F. et al. Angular momentum–induced delays in solid-state photoemission enhanced by intra-atomic interactions. Science 357, 1274–1277 (2017).

    CAS  Google Scholar 

  6. Chen, C. et al. Distinguishing attosecond electron–electron scattering and screening in transition metals. Proc. Natl Acad. Sci. USA 114, E5300–E5307 (2017).

    CAS  Google Scholar 

  7. Tao, Z. et al. Direct time-domain observation of attosecond final-state lifetimes in photoemission from solids. Science 353, 62–67 (2016).

    CAS  Google Scholar 

  8. Kienberger, R. et al. Atomic transient recorder. Nature 427, 817–821 (2004).

    CAS  Google Scholar 

  9. Muller, H. G. Reconstruction of attosecond harmonic beating by interference of two-photon transitions. Appl. Phys. B 74, s17–s21 (2002).

    CAS  Google Scholar 

  10. Schultze, M. et al. Delay in photoemission. Science 328, 1658–1662 (2010).

    CAS  Google Scholar 

  11. Pazourek, R., Nagele, S. & Burgdörfer, J. Attosecond chronoscopy of photoemission. Rev. Mod. Phys. 87, 765–802 (2015).

    CAS  Google Scholar 

  12. Lucchini, M. et al. Light-matter interaction at surfaces in the spatiotemporal limit of macroscopic models. Phys. Rev. Lett. 115, 137401 (2015).

    CAS  Google Scholar 

  13. Locher, R. et al. Energy-dependent photoemission delays from noble metal surfaces by attosecond interferometry. Optica 2, 405–410 (2015).

    CAS  Google Scholar 

  14. Kasmi, L. et al. Effective mass effect in attosecond electron transport. Optica 4, 1492–1497 (2017).

    CAS  Google Scholar 

  15. Ossiander, M. et al. Attosecond correlation dynamics. Nat. Phys. 13, 280–285 (2017).

    CAS  Google Scholar 

  16. Palacios, A., McCurdy, C. W. & Rescigno, T. N. Extracting amplitudes for single and double ionization from a time-dependent wave packet. Phys. Rev. A 76, 043420 (2007).

    Google Scholar 

  17. Pazourek, R., Feist, J., Nagele, S. & Burgdörfer, J. Attosecond streaking of correlated two-electron transitions in helium. Phys. Rev. Lett. 108, 163001 (2012).

    Google Scholar 

  18. Magerl, E. et al. A flexible apparatus for attosecond photoelectron spectroscopy of solids and surfaces. Rev. Sci. Instrum. 82, 063104 (2011).

    CAS  Google Scholar 

  19. Cavalieri, A. L. et al. Intense 1.5-cycle near infrared laser waveforms and their use for the generation of ultra-broadband soft-X-ray harmonic continua. New J. Phys. 9, 242 (2007).

    Google Scholar 

  20. Eisenbud, L. The Formal Properties of Nuclear Collisions. PhD thesis, Princeton Univ. (1948).

  21. Wigner, E. P. Lower limit for the energy derivative of the scattering phase shift. Phys. Rev. 98, 145–147 (1955).

    CAS  Google Scholar 

  22. Smith, F. T. Lifetime matrix in collision theory. Phys. Rev. 118, 349–356 (1960).

    Google Scholar 

  23. Huppert, M., Jordan, I., Baykusheva, D., von Conta, A. & Wörner, H. J. Attosecond delays in molecular photoionization. Phys. Rev. Lett. 117, 093001 (2016).

    Google Scholar 

  24. Heuser, S. et al. Angular dependence of photoemission time delay in helium. Phys. Rev. A 94, 063409 (2016).

    Google Scholar 

  25. Neppl, S. et al. Attosecond time-resolved photoemission from core and valence states of magnesium. Phys. Rev. Lett. 109, 087401 (2012).

    CAS  Google Scholar 

  26. Tanuma, S., Powell, C. J. & Penn, D. R. Calculations of electron inelastic mean free paths. II. Data for 27 elements over the 50–2000 eV range. Surf. Interface Anal. 17, 911–926 (1991).

    CAS  Google Scholar 

  27. Krasovskii, E. E. Attosecond spectroscopy of solids: streaking phase shift due to lattice scattering. Phys. Rev. B 84, 195106 (2011).

    Google Scholar 

  28. Mirhosseini, H., Flieger, M. & Henk, J. Dirac-cone-like surface state in W(110): dispersion, spin texture and photoemission from first principles. New J. Phys. 15, 033019 (2013).

    Google Scholar 

  29. Pi, T.-W., Hong, L.-H. & Cheng, C.-P. Synchrotron-radiation photoemission study of Ba on W(110). Phys. Rev. B 58, 4149–4155 (1998).

    CAS  Google Scholar 

  30. Riemensberger, J. Time-Frequency-Resolved Absolute Time Delay of the Photoelectric Effect. PhD Thesis, Technische Universität München (2018).

    Google Scholar 

  31. Yakovlev, V. S., Gagnon, J., Karpowicz, N. & Krausz, F. Attosecond streaking enables the measurement of quantum phase. Phys. Rev. Lett. 105, 073001 (2010).

    CAS  Google Scholar 

  32. Kazansky, A. K. & Echenique, P. M. Theoretical study of the ionization of an alkali atom adsorbed on a metal surface by a laser-assisted subfemtosecond pulse. Phys. Rev. B 81, 075440 (2010).

    Google Scholar 

  33. Jones, R. G. Halogen adsorption on solid surfaces. Prog. Surf. Sci. 27, 25–160 (1988).

    CAS  Google Scholar 

  34. Jones, R. G. & Dowben, P. A. Reply to comments on “A re-interpretation of the LEED structures formed by iodine on W(110)” by P. A. Dowben and R. G. Jones. Surf. Sci. 116, L228–L231 (1982).

    CAS  Google Scholar 

  35. Dowben, P. A. & Jones, R. G. A re-interpretation of the LEED structures formed by iodine on W(110). Surf. Sci. 105, 334–346 (1981).

    CAS  Google Scholar 

  36. Shirley, D. High-resolution X-ray photoemission spectrum of the valence bands of gold. Phys. Rev. B 5, 4709–4714 (1972).

    Google Scholar 

  37. Quéré, F., Mairesse, Y. & Itatani, J. Temporal characterization of attosecond XUV fields. J. Mod. Opt. 52, 339–360 (2005).

    Google Scholar 

  38. Cutler, J. N., Bancroft, G. M., Sutherland, D. G. & Tan, K. H. Chemical dependence of core-level linewidths and ligand-field splittings: high-resolution core-level photoelectron spectra of I4d levels. Phys. Rev. Lett. 67, 1531–1534 (1991).

    CAS  Google Scholar 

  39. Neppl, S. Attosecond Time-Resolved Photoemission from Surfaces and Interfaces (Technische Universität München, München, 2012).

    Google Scholar 

  40. Gagnon, J., Goulielmakis, E. & Yakovlev, V. S. The accurate FROG characterization of attosecond pulses from streaking measurements. Appl. Phys. B 92, 25–32 (2008).

    CAS  Google Scholar 

  41. Dunin von Przychowski, M., Wiechert, H., Marx, G. K. L. & Schönhense, G. Real-space observation of xenon adsorption and desorption kinetics on graphite (0001) by photoemission electron microscopy. Surf. Sci. 541, 46–58 (2003).

    CAS  Google Scholar 

  42. Schmidt, M. W. et al. General atomic and molecular electronic structure system. J. Comput. Chem. 14, 1347–1363 (1993).

    CAS  Google Scholar 

  43. Schuchardt, K. L. et al. Basis Set Exchange: a community database for computational sciences. J. Chem. Inf. Model. 47, 1045–1052 (2007).

    CAS  Google Scholar 

  44. Feller, D. The role of databases in support of computational chemistry calculations. J. Comput. Chem. 17, 1571–1586 (1996).

    CAS  Google Scholar 

  45. Barbieri, P. L., Fantin, P. A. & Jorge, F. E. Gaussian basis sets of triple and quadruple zeta valence quality for correlated wave functions. Mol. Phys. 104, 2945–2954 (2006).

    CAS  Google Scholar 

  46. Campos, C. T. & Jorge, F. E. Triple zeta quality basis sets for atoms Rb through Xe: application in CCSD(T) atomic and molecular property calculations. Mol. Phys. 111, 167–173 (2013).

    CAS  Google Scholar 

  47. Yanai, T., Tew, D. P. & Handy, N. C. A new hybrid exchange correlation functional using the Coulomb-attenuating method (CAM-B3LYP). Chem. Phys. Lett. 393, 51–57 (2004).

    CAS  Google Scholar 

  48. Perdew, J. P. & Zunger, A. Self-interaction correction to density-functional approximations for many-electron systems. Phys. Rev. B 23, 5048–5079 (1981).

    CAS  Google Scholar 

  49. Natalense, A. P. P. & Lucchese, R. R. Cross section and asymmetry parameter calculation for sulfur 1s photoionization of SF6. J. Chem. Phys. 111, 5344–5348 (1999).

    CAS  Google Scholar 

  50. Gianturco, F. A., Lucchese, R. R. & Sanna, N. Calculation of low energy elastic cross sections for electron-CF4 scattering. J. Chem. Phys. 100, 6464–6471 (1994).

    CAS  Google Scholar 

  51. Hockett, P., Frumker, E., Villeneuve, D. M. & Corkum, P. B. Time delay in molecular photoionization. J. Phys. B 49, 095602 (2016).

    Google Scholar 

  52. Nahon, L., Svensson, A. & Morin, P. Experimental study of the 4d ionization continuum in atomic iodine by photoelectron and photoion spectroscopy. Phys. Rev. A 43, 2328–2337 (1991).

    CAS  Google Scholar 

  53. Olney, T. N., Cooper, G. & Brion, C. Quantitative studies of the photoabsorption (4.5–488 eV) and photoionization (9–59.5 eV) of methyl iodide using dipole electron impact techniques. Chem. Phys. 232, 211–237 (1998).

    CAS  Google Scholar 

  54. Amusia, M. Y., Cherepkov, N. A., Chernysheva, L. V. & Manson, S. T. Photoionization of atomic iodine and its ions. Phys. Rev. A 61, 020701 (2000).

    Google Scholar 

  55. Fano, U. Effects of configuration interaction on intensities and phase shifts. Phys. Rev. 124, 1866–1878 (1961).

    CAS  Google Scholar 

  56. Burgdörfer, J. Dynamical image charge effects on convoy electron emission from solid surfaces. Nucl. Instrum. Methods B 24–25, 139–142 (1987).

    Google Scholar 

  57. Weaver, J. H., Olson, C. G. & Lynch, D. W. Optical properties of crystalline tungsten. Phys. Rev. B 12, 1293–1297 (1975).

    CAS  Google Scholar 

  58. Connerade, J. P. in Giant Resonances in Atoms, Molecules, and Solids (eds Connerade, J. P., Esteva, J. M. & Karnatak, R. C.) 3–23 (NATO Sci. Ser. B, Vol. 151, Springer Science+Business Media, New York, 1987).

  59. Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).

    CAS  Google Scholar 

  60. Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 1758–1775 (1999).

    CAS  Google Scholar 

  61. Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metals. Phys. Rev. B 47, 558–561 (1993).

    CAS  Google Scholar 

  62. Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium. Phys. Rev. B 49, 14251–14269 (1994).

    CAS  Google Scholar 

  63. Lemell, C., Solleder, B., Tőkési, K. & Burgdörfer, J. Simulation of attosecond streaking of electrons emitted from a tungsten surface. Phys. Rev. A 79, 062901 (2009).

    Google Scholar 

  64. Salvat, F., Jablonski, A. & Powell, C. J. ELSEPA — Dirac partial-wave calculation of elastic scattering of electrons and positrons by atoms, positive ions and molecules. Comput. Phys. Commun. 165, 157–190 (2005).

    CAS  Google Scholar 

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Acknowledgements

We acknowledge discussions with M. Schultze, experimental support by A. Kim and A. Schiffrin and infrastructural support by F. Krausz. This work was supported by the Max Planck Society, the Deutsche Forschungsgemeinschaft Cluster of Excellence, Munich Centre for Advanced Photonics, a Consolidator Grant from the European Research Council (ERC-2014-CoG AEDMOS), LASERLAB-EUROPE (grant agreement number 654148, European Union’s Horizon 2020 research and innovation programme), FWF Austria (SFB-041 ViCoM, SFB-049 NextLite) and COST Action CM1204 (XLIC). Calculations were performed using the Vienna Scientific Cluster (VSC).

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Nature thanks M. Chini and T. Fennel for their contribution to the peer review of this work.

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Author notes

  1. These authors contributed equally: M. Ossiander, J. Riemensberger

Authors and Affiliations

  1. Physik-Department, Technische Universität München, Garching, Germany

    M. Ossiander, J. Riemensberger, M. Mittermair, M. Schäffer, A. Duensing, M. S. Wagner, R. Heider, M. Wurzer, M. Gerl, M. Schnitzenbaumer, J. V. Barth, P. Feulner & R. Kienberger

  2. Max-Planck-Institut für Quantenoptik, Garching, Germany

    M. Ossiander, J. Riemensberger, M. Schäffer, M. Gerl & R. Kienberger

  3. Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, Germany

    S. Neppl

  4. Institute for Theoretical Physics, Vienna University of Technology, Vienna, Austria

    F. Libisch, C. Lemell & J. Burgdörfer

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  1. M. Ossiander
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Contributions

M.O., J.R., S.N., M.M., M. Schäffer, A.D., M.S.W., R.H., M.W., M.G. and M. Schnitzenbaumer carried out the experiments. M.O. and J.R. analysed the experimental data. F.L., C.L. and J.B. performed the electron transport and DFT calculations. M.O. wrote the initial manuscript. J.V.B., P.F. and R.K. supervised the study. All authors discussed and reviewed the manuscript.

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Correspondence to M. Ossiander or R. Kienberger.

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Extended data figures and tables

Extended Data Fig. 1 I/W(110) and W(110) measurements.

a, Main panel, XUV I/W(110) photoelectron spectra taken at 105 eV central photon energy for different adsorbate surface coverages (key in top left inset). Three effects are observable with decreasing iodine surface coverage: a decrease of the I4d peak intensity, an increase of the W4f peak intensity due to reduced inelastic scattering, and a shape change of the valence-electron peak towards a clean tungsten spectrum. The iodine surface density was calibrated by taking a full monolayer I/W(110) photoelectron spectrum as a reference before thermal desorption and comparing the I4d photoelectron flux before and after the thermal desorption of iodine. Because the iodine surface coverage saturates, this allows for a reliable coverage calibration. Top centre inset, illustration of the employed Shirley background (BG) subtraction scheme; top right inset, the magnified valence photoelectron spectrum. b, Relative photoemission delays for I/W(110). Both W4f to I4d (blue) and valence to I4d (red) delays are shown. All individual measurements are depicted by crosses, averages for individual coverages are depicted by circles. Vertical error bars mark 95% confidence assuming a Student’s t-distribution and horizontal error bars mark maximum errors. The blue line represents a linear regression to the W4f to I4d delay (blue line), the shaded area represents the 95% confidence interval of this model. c, Attosecond streaking delay measurements on a pristine W(110) surface. The W4f−CB emission delay (blue circles and histogram) as a function of the time of measurement after the preparation of a pristine surface (yellow) reveals a small deviation of the centre (red, dashed line) of the normal distribution (red, solid line) fit to all measurements from the extrapolation to an instantaneous measurement due to surface contamination. The large number of measurements allows the extraction of the photoemission timing of the clean surface by extrapolation.

Extended Data Fig. 2 Typical streaking spectrogram measured for I/W(110) at 32% of the saturated iodine surface coverage and its reconstruction.

The first column shows the experimental data, the second column the results of the reconstruction algorithm and the third column their difference. The residual mainly consists of background independent of the XUV−NIR-delay, which is cancelled during the retrieval by differentiating along the delay axis. The three rows focus, from top to bottom, on the streaking of the valence, W4f and I4d photoemission peaks. The XUV−NIR-delay difference between consecutive spectra in the spectrogram is 200 as. The photoemission delay results extracted from this sample spectrogram are \({\rm{\Delta }}{\tau }_{{\rm{W}}4f-{\rm{I}}4d}=81\hspace{1pt}{\rm{as}}\) and \({\rm{\Delta }}{\tau }_{{\rm{Valence}}-{\rm{I}}4d}=14\hspace{1.5pt}{\rm{as}}\).

Extended Data Fig. 3 Gas-phase iodine/helium measurements.

a, Unstreaked XUV photoelectron spectra of iodoethane (red) and an iodoethane/helium mixture (blue) recorded at 105 eV central photon energy. Electrons emitted through the N4,5VV Auger process are spectrally separated from all timed photoelectron peaks. b, Relative I4d−He1s photoemission delay for different mixture compositions of iodoethane and helium. Shown are individual measurements (blue circles), linear regression (red line) and the 95% confidence interval of the regression (shaded area). c, Histograms (blue) of the individual relative photoemission delay measurements (yellow) between He1s and I4d electrons in iodomethane and iodoethane at 105 eV photon energy and normal-distribution fits to the data (red).

Extended Data Fig. 4 Results of DFT calculations.

a, DFT-derived electron density in the surface bandgap of a clean W(110) surface. A 2D cut through the \((1\bar{1}0)\) plane, perpendicular to the (110) surface, is shown. Tungsten atoms are indicated as black circles. Second-layer atoms are projected onto the plane of the cut. The inelastic mean free path λIMFP for conduction-band photoelectrons is marked as a guide to the eye. b, Energy-resolved density of states for an iodine-covered W(110) surface. The red dashed line represents the density of states in the proximity of the top-layer tungsten atoms and the blue dashed line represents the density of states near the iodine adsorbates. The full lines are folded with the spectrum of the experimental XUV pulse. The yellow line represents the full density of states of the iodine covered tungsten surface folded with the experimental XUV spectrum. See Methods for details of ‘jellium edge’ and EF.

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Ossiander, M., Riemensberger, J., Neppl, S. et al. Absolute timing of the photoelectric effect. Nature 561, 374–377 (2018). https://doi.org/10.1038/s41586-018-0503-6

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Keywords

  • Chronoscope
  • Electron Wave Packet
  • Attosecond Precision
  • Exit Delay
  • Giant Dipole Resonance

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