Imperial College London

Dr Allan Johnson

Faculty of Natural SciencesDepartment of Physics

Academic Visitor



allan.johnson13 CV




Blackett LaboratorySouth Kensington Campus





I work with the Blackett Laser Consortium on attosecond, strong field, and ultrafast physics. By using extremely short and/or fast laser pulses, we can examine extremely fast quantum dynamics. With a new generation of laser sources and laser technologies boasting high intensities, short wavelengths, and ultrafast durations, we are now able to image and control matter at an unprecedented level.

My work with the Laser Consortium has two main thrusts - developing new sources for attosecond physics, and using them to track charge migration inside molecules. We have developed new few-cycle duration IR driving sources for generation of soft X-ray attosecond pulses, and generated attosecond pulses in the so-called water window region (284-540 eV).

More recently I have been focused on using ultrafast optical and X-ray sources to examine correlated materials (such as superconductors). More information at



Selected Publications

Journal Articles

Johnson A, Austin D, Wood D, et al., 2018, High-flux soft x-ray harmonic generation from ionization-shaped few-cycle laser pulses, Science Advances, Vol:4, ISSN:2375-2548

Sanchez Gonzalez A, Micaelli P, Olivier C, et al., 2017, Accurate prediction of X-ray pulse properties from a free-electron laser using machine learning, Nature Communications, Vol:8, ISSN:2041-1723

Johnson AS, Miseikis L, Wood DA, et al., 2016, Measurement of sulfur L2,3 and carbon K edge XANES in a polythiophene film using a high harmonic supercontinuum, Structural Dynamics, Vol:3, ISSN:2329-7778

Pitzer M, Kunitski M, Johnson AS, et al., 2013, Direct Determination of Absolute Molecular Stereochemistry in Gas Phase by Coulomb Explosion Imaging, Science, Vol:341, ISSN:0036-8075, Pages:1096-1100

Shafir D, Soifer H, Vozzi C, et al., 2013, Trajectory-Resolved Coulomb Focusing in Tunnel Ionization of Atoms with Intense, Elliptically Polarized Laser Pulses, Physical Review Letters, Vol:111, ISSN:0031-9007

Salvail JZ, Agnew M, Johnson AS, et al., 2013, Full characterization of polarization states of light via direct measurement, Nature Photonics, Vol:7, ISSN:1749-4885, Pages:316-321

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