Attosecond Nonlinear Optics

Extreme nonlinear optics – exquisite quantum control over short wavelength light

Ever since the invention of the visible laser over 50 years ago, scientists have been striving to create lasers that generate coherent beams at shorter wavelengths i.e. the extreme UV (EUV) and soft X-ray (SXR) regions of the spectrum. This quest has led to the construction of large facilities, such as kilometer-scale x-ray free-electron lasers, to reach the keV photon energy region. Ultimately however, to be broadly accessible for science, medicine and industry, laser-like (i.e. coherent) x-ray sources need to be much smaller and cheaper.

Fortunately, high harmonic generation (HHG)—the coherent equivalent of the Roentgen x-ray tube—represents a unique new quantum technology for generating ultrafast coherent beams spanning the VUV, EUV and keV regions of the spectrum. In HHG, a femtosecond laser pulse is focused into a gas – where it manipulates the quantum wavefunction of an electron, to create a nanoscale dipole antenna. By confining the gas in a waveguide geometry, the HHG process can be very efficient, and useful for a broad range of applications in materials and chemical science. Moreover, by changing the color, polarization and phase of the femtosecond laser beam, the spectrum, pulse duration, polarization, phase and shape of the generated HHG beam can be controlled – on exquisite sub-Å and sub-attosecond (10^-18 s) length and time scales. This has allowed us to develop a unique light source that can be tuned from a 12-octave spanning supercontinuum to isolated spectral peaks with full temporal and spatial coherence and with arbitrary polarization and orbital angular momentum charge.

In the future, laser-like coherent hard X-ray high harmonic beams may well become a feasible alliterative to the lightbulb-like x-ray tube that is still ubiquitous in medical imaging – more than a century after Roentgen’s discovery.

Related Publications

1. D. Couch, D. Hickstein, S. Backus, D. Winters, J. Ramirez, S. Domingue, M. Kirchner, C. Durfee, M. Murnane, H. Kapteyn, “A 1 MHz ultrafast vacuum UV source via highly cascaded harmonic generation in negative-curvature hollow-core fibers,” Optica 7, 832 (2020). doi.org/10.1364/OPTICA.395688
2. L. Rego, K. M. Dorney, N. J. Brooks, Q. L. Nguyen, C.-T. Liao, J. San Román, D. E. Couch, A. Liu, E. Pisanty, M. Lewenstein, L. Plaja, H. C. Kapteyn, M. M. Murnane, C. Hernández-García, “Generation of extreme-ultraviolet beams with time-varying orbital angular momentum,” Science 364, eaaw9486 (2019). Featured on cover. DOI:10.1126/science.aaw9486 
3. K. M. Dorney, L. Rego, N. J. Brooks, J. San Román, C.-T. Liao, J. L. Ellis, D. Zusin, C. Gentry, Q. L. Nguyen, J. M. Shaw, A. Picón, L. Plaja, H. C. Kapteyn, M. M. Murnane, C. Hernández-García, “Controlling the polarization and vortex charge of attosecond high-harmonic beams via simultaneous spin-orbit momentum conservation,” Nature Photonics 13, 123–130 (2019). DOI: 10.1038/s41566-018-0304-3
4. C. Chen, Z. Tao, C. Hernández-García, P. Matyba, A. Carr, R. Knut, O. Kfir, D. Zusin, C. Gentry, P. Gychtol, O. Cohen, L. Plaja, A. Becker, A. Jaron-Becker, H. Kapteyn, M. Murnane, “Tomographic Reconstruction of Circularly Polarized High Harmonic Fields: 3D Attosecond Metrology,” Science Advances 2, e1501333 (2016).
5. T. Fan, P. Gychtol, R. Knut, C. Hernández-García, D. D. Hickstein, D. Zusin, C. Gentry, F. Dollar, C. A. Mancuso, C. Hogle, O. Kfir, D. Legut, K. Carva, J. L. Ellis, K. Dorney, C. Chen, O. Shpyrko, E. E. Fullerton, O. Cohen, P. M. Oppeneer, D. B. Milošević, A. Becker, A. Jaron-Becker, T. Popmintchev,  M. Murnane, H. Kapteyn, “Bright Circularly Polarized Soft X-Ray High Harmonics for X-Ray Magnetic Circular Dichroism,” PNAS 112 (46) 14206–14211 (2015). DOI: 10.1073/pnas.1519666112
6. D. Popmintchev, C. Hernández-García, F. Dollar, C. Mancuso, J. Pérez-Hernández, M.C. Chen, A. Hankla, X. Gao, B. Shim, A. Gaeta, M. Tarazkar, D. Romanov, R. Levis, J. Gaffney, M. Foord, S. Libby, A. Jaron-Becker, A. Becker, L. Plaja, M. Murnane, H. Kapteyn, T. Popmintchev, “Efficient soft X-ray high harmonic generation in multiply-ionized plasmas: the ultraviolet surprise,” Science 350, 1225 (2015).
7. Ofer Kfir, Patrik Grychtol, Emrah Turgut, Ronny Knut Dmitriy Zusin, Dimitar Popmintchev, Tenio Popmintchev, Hans Nembach, Justin M. Shaw, Avner Fleicher, Henry Kapteyn, Margaret Murnane and Oren Cohen, “Generation of bright circularly-polarized extreme ultraviolet high harmonics for magnetic circular dichroism spectroscopy,” Nature Photonics 9, 99–105 (2015).
8. M.-C. Chen, C. Hernández-García, C. Mancuso, F. Dollar, B. Galloway, D. Popmintchev, P.-C. Huang,  B. Walker, L. Plaja, A. Jaron-Becker, A. Becker, T. Popmintchev, M.M. Murnane, H. C. Kapteyn, “Generation of Bright Isolated Attosecond Soft X-Ray Pulses Driven by Multi-Cycle Mid-Infrared Lasers,” PNAS 111 (23) E2361-E2367 (2014); doi:10.1073/pnas.1407421111.
9. C. Hernández-García, J.A. Pérez-Hernández, T. Popmintchev, M. Murnane, H. Kapteyn, A. Jaron-Becker, A.Becker, and L. Plaja, “Zeptosecond keV pulse trains and waveforms driven by mid-infrared laser pulses,” Physical Review Letters 111, 033002 (2013).
10. Tenio Popmintchev, Ming-Chang Chen, Dimitar Popmintchev, Paul Arpin, Skirmantas Ališauskas, Giedrius Andriukaitis, Tadas Balčiunas, Audrius Pugzlys, Andrius Baltuška, Bonggu Shim, Alex Gaeta, Margaret Murnane, Henry Kapteyn, “Bright Coherent Ultrahigh Harmonics in the keV X-Ray Regime from Mid-Infrared Femtosecond Lasers,” Science 336, 1287 (2012).
11. M.C. Chen, P. Arpin, T. Popmintchev, M. Gerrity, B. Zhang, M. Seaberg, M.M. Murnane and H.C. Kapteyn, “Bright, Coherent, Ultrafast Soft X-Ray Harmonics Spanning the Water Window from a Tabletop Source,” Physical Review Letters 105, 173901 (2010). Featured on cover.
12. T. Popmintchev, M.C. Chen, P. Arpin, M.M. Murnane and H.C. Kapteyn, “The Attosecond Nonlinear Optics of Bright Coherent X-Ray Generation,” Nature Photonics 4, 822 (2010). Featured on cover.
13. I. Thomann, A. Bahabad, R. Trebino, M. M. Murnane and H. C. Kapteyn, “Characterizing isolated attosecond pulses from hollow-core waveguides using multi-cycle driving pulses,” Optics Express 17, 4611 (2009).
14. Tenio Popmintchev, Ming-Chang Chen, Alon Bahabad, Michael Gerrity, Pavel Sidorenko, Oren Cohen, Ivan P. Christov, Margaret M. Murnane, and Henry C. Kapteyn, “Phase matched upconversion of coherent ultrafast laser light into the soft and hard x-ray regions of the spectrum,” Proceedings of the National Academies of the US 106 (26), 10516 (2009).
15. T. Popmintchev, M.C. Chen, O. Cohen, M.E. Grisham, J.J. Rocca, M.M. Murnane, H.C. Kapteyn, “Phase-Matching of High Harmonics Driven by Mid-Infrared Light,” Optics Letters 33, 2128 (2008).
16. Henry C. Kapteyn, Oren Cohen, Ivan Christov, Margaret M. Murnane, “Harnessing Attosecond Science in the Quest for Coherent X-Rays,” Science 317, 775 (2007).
17. Henry C. Kapteyn, Margaret M. Murnane and Ivan P. Christov, “Coherent X-Rays from Lasers: Applied Attosecond Science,” invited article, Physics Today, 58(3), 39 (2005).
18. Randy Bartels, Ariel Paul, H. Hans Green, Henry Kapteyn, Margaret Murnane, Sterling Backus, Ivan Christov, Yanwei Liu, David Attwood, Chris Jacobsen, “Generation of spatially coherent light at extreme ultraviolet wavelengths,” Science 297, 376 (2002).
19. R A. Rundquist, C. Durfee, Z. Chang, C. Herne, H. Kapteyn and M. Murnane, “Phase Matching of Soft-X-Ray Harmonic Emission in Hollow-Core Fibers,” Science 280, 1412 (1998).