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Controlling X-rays with light


Ultrafast X-ray science is an exciting frontier that promises the visualization of electronic, atomic and molecular dynamics on atomic time and length scales. A largely unexplored area of ultrafast X-ray science is the use of light to control how X-rays interact with matter. To extend control concepts established for long-wavelength probes to the X-ray regime, the optical control field must drive a coherent electronic response on a timescale comparable to femtosecond core-hole lifetimes. An intense field is required to achieve this rapid response. Here, an intense optical control pulse is observed to efficiently modulate photoelectric absorption for X-rays and to create an ultrafast transparency window. We demonstrate an application of X-ray transparency relevant to ultrafast X-ray sources: an all-photonic temporal cross-correlation measurement of a femtosecond X-ray pulse. The ability to control X-ray–matter interactions with light will create new opportunities for present and next-generation X-ray light sources.

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Figure 1: Relevant atomic states contributing to X-ray absorption.
Figure 2: X-ray absorption spectrum for Ne in the absence of a coupling laser.
Figure 3: The fractional change in X-ray transmission induced by the coupling laser in the parallel polarization configuration (ɛLɛX).
Figure 4: Polarization dependence of the fractional change in X-ray transmission and the calculated X-ray absorption cross-section for laser-dressed neon.
Figure 5: Cross-correlation measurement of the femtosecond X-ray pulse duration from the ALS slicing source.
Figure 6: Layout of the femtosecond spectroscopy beamline at the ALS.


  1. Cavalleri, A. et al. Band-selective measurements of electron dynamics in VO2 using femtosecond near-edge X-ray absorption. Phys. Rev. Lett. 95, 067405 (2005).

    ADS  Article  Google Scholar 

  2. Fritz, D. M. et al. Ultrafast bond softening in bismuth: Mapping a solid’s interatomic potential with X-rays. Science 315, 633–636 (2007).

    ADS  Article  Google Scholar 

  3. Bressler, Ch. et al. Femtosecond XANES study of the light-induced spin crossover dynamics in an iron (II) complex. Science 323, 489–492 (2009).

    ADS  Article  Google Scholar 

  4. Chen, L. X. Taking snapshots of photoexcited molecules in disordered media by using pulsed synchrotron X-rays. Angew. Chem. Int. Edn 43, 2886–2905 (2004).

    Article  Google Scholar 

  5. Bressler, C. & Chergui, M. Ultrafast X-ray absorption spectroscopy. Chem. Rev. 104, 1781–1812 (2004).

    Article  Google Scholar 

  6. Hertlein, M. P. et al. Inner-shell ionization of potassium atoms ionized by a femtosecond laser. Phys. Rev. A. 73, 062715 (2006).

    ADS  Article  Google Scholar 

  7. Young, L. et al. X-ray microprobe of orbital alignment in strong-field ionized atoms. Phys. Rev. Lett. 97, 083601 (2006).

    ADS  Article  Google Scholar 

  8. Peterson, E. R. et al. An X-ray probe of laser aligned molecules. Appl. Phys. Lett. 92, 094106 (2008).

    ADS  Article  Google Scholar 

  9. Harris, S. E. Electromagnetically induced transparency. Phys. Today 50, 36–42 (1997).

    Article  Google Scholar 

  10. Fleischhauer, M., Imamoglu, A. & Marangos, J. P. Electromagnetically induced transparency: Optics in coherent media. Rev. Mod. Phys. 77, 633–673 (2005).

    ADS  Article  Google Scholar 

  11. Harris, S. E. Nonlinear optics at low light levels. Phys. Rev. Lett. 82, 4611–4614 (1999).

    ADS  Article  Google Scholar 

  12. Loh, Z. H., Greene, C. H. & Leone, S. R. Femtosecond induced transparency and absorption in the extreme ultraviolet by coherent coupling of the He 2s2p (1P0) and 2p2 (1Se) double excitation states with 800 nm light. Chem. Phys. 350, 7–13 (2008).

    Article  Google Scholar 

  13. Arthur, J. et al. Linac coherent light source (LCLS) design study report, SLAC Report No. SLAC-R-593, UC-414 (SLAC, 2002).

  14. Altarelli, M. et al. DESY Report No. 2006-097 (DESY, 2006).

  15. Tanaka, T. & Shintake, T. SCSS X-FEL conceptual design report, (RIKEN Harima Institute/Spring-8, 2005).

  16. DeCamp, M. F. et al. Coherent control of pulsed X-ray beams. Nature 413, 825–828 (2001).

    ADS  Article  Google Scholar 

  17. Grigoriev, A. et al. Subnanosecond piezoelectric X-ray switch. Appl. Phys. Lett. 89, 021109 (2006).

    ADS  Article  Google Scholar 

  18. Buth, C., Santra, R. & Young, L. Electromagnetically induced transparency for X-rays. Phys. Rev. Lett. 98, 253001 (2007).

    ADS  Article  Google Scholar 

  19. Brumer, P. W. & Shapiro, M. Principles of the Quantum Control of Molecular Processes (Wiley, 2003).

    MATH  Google Scholar 

  20. Schweigert, I. V. & Mukamel, S. Coherent ultrafast core-hole correlation spectroscopy: X-ray analogues of multidimensional NMR. Phys. Rev. Lett. 99, 163001 (2007).

    ADS  Article  Google Scholar 

  21. Varma, H. R., Pan, L., Beck, D. R. & Santra, R. X-ray absorption near-edge structure of laser-dressed neon. Phys. Rev. A 78, 065401 (2008).

    ADS  Article  Google Scholar 

  22. Buth, C. & Santra, R. Theory of X-ray absorption by laser-dressed atoms. Phys. Rev. A 75, 033412 (2007).

    ADS  Article  Google Scholar 

  23. Autler, S. H. & Townes, C. H. Stark effect in rapidly varying fields. Phys. Rev. 100, 703–722 (1955).

    ADS  Article  Google Scholar 

  24. Littman, M. G., Kash, M. M. & Kleppner, D. Field-ionization processes in excited atoms. Phys. Rev. Lett. 41, 103–107 (1978).

    ADS  Article  Google Scholar 

  25. Agrawal, G. S. Nature of the quantum interference in electromagnetically-field-induced control of absorption. Phys. Rev. A 55, 2467–2470 (1997).

    ADS  MathSciNet  Article  Google Scholar 

  26. Imamoglu, A. & Harris, S. E. Lasers without inversion: Interference of dressed lifetime-broadened states. Opt. Lett. 14, 1344–1346 (1989).

    ADS  Article  Google Scholar 

  27. Steier, C. et al. Successful completion of the femtosecond slicing upgrade at the ALS. Particle Accelerator Conference, PAC. IEEE 25–29, 1194–1196 (2007).

    ADS  Google Scholar 

  28. Meyer, M. et al. Two-color photoionization in xuv free-electron and visible laser fields. Phys. Rev. A 74, 011401(R) (2006).

    ADS  Article  Google Scholar 

  29. Schoenlein, R. W. et al. Femtosecond pulses of synchrotron radiation: A new tool for ultrafast time-resolved X-ray spectroscopy. Science 287, 2237–2240 (2000).

    ADS  Article  Google Scholar 

  30. Khan, S. et al. Femtosecond undulator radiation from sliced electron bunches. Phys. Rev. Lett. 97, 074801 (2006).

    ADS  Article  Google Scholar 

  31. Beaud, P. et al. Spatiotemporal stability of a femtosecond hard–X-ray undulator source studied by control of coherent optical phonons. Phys. Rev. Lett. 99, 174801 (2007).

    ADS  Article  Google Scholar 

  32. Coreno, M. et al. Measurement and ab initio calculation of the Ne photoabsorption spectrum in the region of the K edge. Phys. Rev. A 59, 2492–2497 (1999).

    ADS  Article  Google Scholar 

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We thank C. Buth and S.E. Harris for enlightening discussions and D.L. Ederer, T. Weber, R.W. Schoenlein and P. Heimann for experimental support during early stages of this project. This work was supported by the Chemical Sciences, Geosciences, and Biosciences Division of the Office of Basic Energy Sciences, Office of Science, US Department of Energy, under Contract No. DE-AC02-06CH11357 and DE-AC02-05CH11231. This work was carried out at the Advanced Light Source, Lawrence Berkeley National Laboratory, and was supported by the Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under Contract No. DE-AC02-05CH11231.

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Authors and Affiliations



T.E.G., M.P.H., A.B., S.H.S. and L.Y. contributed to the design of the experiment. T.E.G., M.P.H. and B.R. were responsible for the femtosecond X-ray beamline and control laser performance. T.E.G., M.P.H., S.H.S., T.K.A., J.V.T., E.P.K., B.K. and L.Y. collected the data. H.R.V. and R.S. carried out the supporting theoretical calculations. Data analysis and interpretation were done by S.H.S., T.E.G., M.P.H., E.P.K., R.S. and L.Y.

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Correspondence to L. Young.

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Glover, T., Hertlein, M., Southworth, S. et al. Controlling X-rays with light. Nature Phys 6, 69–74 (2010).

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