Kapteyn-Murnane Group Spin Dynamics

Spin Dynamics

Direct light-induced spin manipulation on few-femtosecond timescales.

Direct light-induced spin manipulation on few-femtosecond timescales.听High harmonic based ARPES combined with element-specific magneto-optic probes uncovered a fundamentally new understanding of how magnets respond to light. In Ni, a new super-excited magnetic state is created, launching a magnetic phase transition within <20 fs. In Co2MnGe and Fe50Ni50, spin polarization can be directly transferred from one element to another in the process of absorbing a photon. This is the fastest route demonstrated for manipulating magnetic materials to听date.

Capturing the fastest spin dynamics in magnetic materials

Magnetism has been the subject of scientific inquiry for more than 2000 years. However, it is still an incompletely understood phenomenon. The fundamental length and time scales for magnetic phenomena range from 脜 (exchange lengths) and sub-femtoseconds (exchange splitting) on up. Furthermore, a detailed understanding of nanoscale magnetism is critical in the 21st century with dramatic increases in data usage and the the critical need for faster, energy-efficient nanodevices. However, a comprehensive microscopic model of how spins, electrons, photons and phonons interact does not yet exist. This understanding is fundamentally constrained in large part by a limited ability to directly observe magnetism on all relevant time and length scales - and tools for addressing these questions have only recently become available.

Ultrafast X-ray pulses make it possible to probe element-specific spin dynamics in multi-component magnetic systems, providing rich new information not accessible using visible light. Our recent research has shown that extreme ultraviolet (EUV) high harmonic beams are ideal for capturing the fastest spin dynamics in magnetic materials.[1-24] By combining HHG sources with new spectroscopic and imaging techniques, we have made a series of new discoveries. In exciting recent work, we showed that light can manipulate spins in many materials on few-femtosecond to attosecond timescales. This could not be observed previously, because many spectroscopic probes average over all excitations and sample depths - and are simply not sensitive to the unique laser-induced spin states present in the material. Key to uncovering this new understanding was a suite of correlated high harmonic based spectroscopies (time- and angle-resolved photoemission (EUV ARPES), combined with element-specific magneto-optic probes (e.g., EUV MOKE, XMCD), that make it possible to detect unique spin excitations present in the material, as illustrated in the Figure. For example, direct (near-instantaneous) light-induced spin transfer can occur between two elements in magnetic materials, during the light pulse itself鈥撯揳chieving the fastest manipulation of spins to date.

Looking to the future, it is now possible to extend these new spectroscopy and imaging measurements to the听L听absorption edges of magnetic media in the soft x-ray region of the spectrum. Recent advances in generating bright, coherent, x-rays from femtosecond lasers in the keV region of the spectrum make this feasible for the first time. Imaging of buried magnetic structures, domain interactions, strongly coupled nano layers, and spin dynamics will all be accessible with femtosecond time and nanometer spatial resolution.

Related Publications
  1. P. Tengdin, C. Gentry, A. Blonsky, D. Zusin, M. Gerrity, L. Hellbr眉ck, J. Shaw, Y. Kvashnin, E. K. Delczeg-Czirjak, M. Arora, H. Nembach, T. J. Silva, S. Mathias, M. Aeschlimann, H. C. Kapteyn, D. Thonig, K. Koumpouras, O. Eriksson, M. Murnane,听鈥淒irect light-induced spin transfer between different elements in a spintronic Heusler material via femtosecond laser excitation,鈥听Science Advances 6, eaaz1100, (2020).听
  2. M. Hofherr, S. H盲user, J. K. Dewhurst, P. Tengdin, S. Sakshath, H. T. Nembach, S. T. Weber, J. M. Shaw, T. J. Silva, H. C. Kapteyn, M. Cinchetti, B. Rethfeld, M. M. Murnane, D. Steil, B. Stadtm眉ller, S. Sharma, M. Aeschlimann, S. Mathias,听鈥淯ltrafast optically induced spin transfer in ferromagnetic alloys,鈥听Science Advances 6, eaay8717 (2020).听
  3. X. Shi, C.-T. Liao, Z. Tao, E. Cating-Subramanian, M. M. Murnane, C. Hern谩ndez-Garc铆a, H. C. Kapteyn, 鈥淎ttosecond light science and its application for probing quantum materials, Invited paper, JPhys Photonics/JPhys B Attosecond focus issue 53, 184008 (2020).听
  4. R. Schoenlein, T. Elsaesser, K. Holldack, Z. Huang, H. Kapteyn, M. Murnane, M. Woerner,听鈥淩ecent advances in ultrafast X-ray sources,鈥听Phil. Trans. R. Soc. A 377: 20180384 (2019).听
  5. P. Tengdin, W. You, C. Chen, X. Shi, D. Zusin, Y. Zhang, C. Gentry, A. Blonsky, M. Keller, P. Oppeneer, H. Kapteyn, Z. Tao, M. Murnane,听鈥淐ritical behavior within 20fs drives the out-of-equilibrium laser-induced magnetic phase transition in nickel,鈥听Science Advances 4, 9744 (2018).
  6. W. You, P.听 Tengdin, C. Chen, X. Shi, D. Zusin, Y. Zhang, C. Gentry, A. Blonsky, M. Keller, P. M. Oppeneer, H. Kapteyn, Z. Tao, M. Murnane,听鈥淩evealing the nature of the ultrafast magnetic phase transition in Ni by correlating extreme ultraviolet magneto-optic and photoemission spectroscopies,鈥听Physical Review Letters 121, 077204 (2018).听
  7. M. Hofherr, S. Moretti, J. Shim, S. H盲user, N.Y. Safonova, M. Stiehl, A. Ali, S. Sakshath, J.W. Kim, D.H. Kim, H.J. Kim, J.I. Hong, H. C. Kapteyn, M. M. Murnane, M. Cinchetti, D. Steil, S. Mathias, B. Stadtm眉ller, M. Albrecht, D.E. Kim, U. Nowak, M. Aeschlimann,听鈥淚nduced vs. intrinsic magnetic moments in ultrafast magnetization dynamics,鈥听Physical Review B 98, 174419 (2018).听. Also selected as an Editor鈥檚 Suggestion.
  8. D. Zusin, P. Tengdin, M. Gopalakrishnan, C. Gentry, A. Blonsky, M. Gerrity, D. Legut, J. Shaw, H. Nembach, T. Silva, P. Oppeneer, H. Kapteyn, M. Murnane,听鈥淒irect measurement of the static and transient magneto-optical permittivity of cobalt across the entire听M-edge in a reflection geometry by use of polarization scanning,鈥听Physical Review B 97, 024433 (2018).听
  9. S. Eich, M. Pl枚tzing, M. Rollinger, S. Emmerich, R. Adam, C. Chen, H. C. Kapteyn, M. M. Murnane, L. Plucinski, D. Steil, B. Stadtm眉ller, M. Cinchetti, M. Aeschlimann, C. M. Schneider, S. Mathias,听鈥淏and-structure evolution during the ultrafast ferromagnetic-paramagnetic phase transition in cobalt,鈥听Science Advances 3, e1602094 (2017).听
  10. C. Chen, Z. Tao, A. Carr, P. Matyba, T. Szilv谩si, S. Emmerich,听 M. Piecuch, , M. Keller, D. Zusin, S. Eich, M. Rollinger, W. You, S. Mathias, U. Thumm, M. Mavrikakis, M. Aeschlimann, P. Oppeneer, H. Kapteyn, M. Murnane,听鈥淒istinguishing attosecond electron-electron scattering and screening in transition metals,鈥听PNAS 114 (27) E5300鈥揈5307 (2017).听
  11. C. A. Mancuso, K. M. Dorney, D. D. Hickstein, J. L. Chaloupka, X-M. Tong, J. L. Ellis, H. C. Kapteyn, M. M.听 Murnane,听鈥淥bservation of ionization enhancement in two-color circularly polarized laser fields,鈥听Physical Review A 96, 023402 (2017).听
  12. E. Turgut, D. Zusin, D. Legut, , K. Carva, R. Knut, J. M. Shaw, C. Chen, Z. Tao, H.听 T. Nembach, T. Silva, S. Mathias, M. Aeschlimann, P. M. Oppeneer, H.C. Kapteyn, M. M. Murnane, P. Grychtol,听鈥淪toner vs Heisenberg: Ultrafast exchange reduction and magnon generation during laser-induced demagnetization,鈥听Physical Review B 94, 220408(R) (2016). Also selected as Editor鈥檚 Suggestion.听
  13. S. Mathias, S. Eich, J. Urbancic, S. Michael, A.V. Carr, S. Emmerich, A. Stange, T. Popmintchev, T. Rohwer, M. Wiesenmayer, A. Ruffing, S. Jakobs, S. Hellmann, P. Matyba, C. Chen, L. Kipp, M. Bauer, H. C. Kapteyn, H. C. Schneider, K. Rossnagel, M. M. Murnane, M. Aeschlimann,听鈥淪elf-amplified photo-induced gap quenching in a correlated electron material,鈥听Nature Communications 7, 12902 (2016).听
  14. O. Kfir, P. Grychtol, E. Turgut, R. Knut, D. Zusin, A. Fleischer, E. Bordo, T. Fan, D. Popmintchev, T. Popmintchev, H. Kapteyn, M. Murnane, O. Cohen,听鈥淗elicity-selective phase-matching and quasi-phase matching of circularly polarized high-order harmonics: towards chiral attosecond pulses,鈥听invited paper, Journal of Physics B: At. Mol. Opt. Phys. 49 (2016) 123501.听
  15. K. M. Hoogeboom-Pot, E. Turgut, J. N. Hernandez-Charpak, J. M. Shaw, H. C. Kapteyn, M. M. Murnane, D. Nardi,听鈥淣ondestructive measurement of the evolution of layer-specific mechanical properties in sub-10 nm bilayer films,鈥听Nano Letters 16 (8), 4773鈥4778 (2016).听
  16. O. Kfir, P. Grychtol, E. Turgut, R. Knut, D. Zusin, D. Popmintchev, T. Popmintchev, H. Nembach, J. M. Shaw, A. Fleischer, H. Kapteyn, M. Murnane, O. Cohen,听鈥淕eneration of bright phase-matched circularly-polarized extreme ultraviolet high harmonics,鈥听Nature Photonics 9, 99鈥105 (2015).听
  17. C. Weier, R. Adam, D. Rudolf, R. Fr枚mter, P. Grychtol, G. Winkler, A. Kobs, H. P. Oepen, H. C. Kapteyn, M. M. Murnane, C. M. Schneider,听鈥淔emtosecond-laser-induced modifications in Co/Pt multilayers studied with tabletop resonant magnetic scattering,鈥听Europhysics Letters 109, 17001 (2015).听
  18. T. Fan, P. Gychtol, R. Knut, C. Hern谩ndez-Garc铆a, D. D. Hickstein, D. Zusin, C. Gentry, F. J. Dollar, C. A. Mancuso, C. W. Hogle, O. Kfir, D. Legut, K. Carva, J. L. Ellis, K. M. Dorney, C. Chen, O. G. Shpyrko, E. E. Fullerton, O. Cohen, P. M. Oppeneer, D. B. Milo拧evi膰, A. Becker, A. Jar贸n-Becker, T. Popmintchev,听 M. M. Murnane, H. C. Kapteyn,听鈥淏right Circularly Polarized Soft X-Ray High Harmonics for X-Ray Magnetic Circular Dichroism,鈥听PNAS 112 (46) 14206鈥14211 (2015).听
  19. S. Mathias, C. La-o-Vorakiat, J. M. Shaw, E. Turgut, P. Grychtol, R. Adam, D. Rudolf, H. T. Nembach, T. J. Silva, M. Aeschlimann, C. M. Schneider, H. C. Kapteyn, M. M. Murnane,听鈥淯ltrafast element-specific magnetization dynamics of complex magnetic materials on a table-top,鈥听invited review paper, Journal of Electron Spectroscopy and Related Phenomena 189, 164 (2013).听
  20. E. Turgut, C. La-o-Vorakiat, J. M.听 Shaw, P. Grychtol, H. T. Nembach, D. Rudolf, R. Adam, M. Aeschlimann, C. M. Schneider, T. J. Silva, M. M. Murnane, H. C. Kapteyn, S. Mathias,听鈥淐ontrolling the competition between optically induced ultrafast spin-flip scattering and spin transport in magnetic multilayers,鈥听Physical Review Letters 110, 197201 (2013).听
  21. D. Rudolf, C. La-O-Vorakiat, M. Battiato, R. Adam, J. M. Shaw, E. Turgut, P. Maldonado, S. Mathias, P. Grychtol, H. T. Nembach, T. J. Silva, M. Aeschlimann, H. C. Kapteyn, M. M. Murnane, C. M. Schneider, P. M. Oppeneer,听鈥淯ltrafast magnetization enhancement in metallic multilayers driven by superdiffusive spin current,鈥听Nature Communications 3, 1037 (2012).听
  22. S. Mathias, C. La-O-Vorakiat, P. Grychtol, Patrick G., Emrah T., J. M. Shaw, R. Adam, H. T. Nembach, M. E. Siemens, S. Eich, C. M. Schneider, T. J. Silva, M. Aeschlimann, M. M. Murnane, and H. C. Kapteyn,听鈥淧robing the timescale of the exchange interaction in a ferromagnetic alloy,鈥听PNAS 109, 4792 (2012).听
  23. C. La-O-Vorakiat, E. Turgut, C. A. Teale, H. C. Kapteyn, M. M. Murnane, S. Mathias, M. Aeschlimann, C. M. Schneider, J. M. Shaw, H. Nembach, T. J. Silva,听鈥淯ltrafast demagnetization measurements using extreme ultraviolet light: Comparison of electronic and magnetic contributions,鈥听Physical Review X 2, 011005 (2012).听
  24. C. La-O-Vorakiat, M. Siemens, M. M. Murnane, H. C. Kapteyn, S. Mathias, M. Aeschlimann, P. Grychtol, R. Adam, C. M. Schneider, J. M. Shaw, H. Nembach, T. J. Silva,听鈥淯ltrafast demagnetization dynamics at the听M听edges of magnetic elements observed using a tabletop high-harmonic soft X-ray source,鈥听Physical Review Letters 103, 257402 (2009).听