TY  - JOUR
A1  - Rettig, L.
A1  - Dornes, C.
A1  - Thielemann-Kuehn, Nele
A1  - Pontius, N.
A1  - Zabel, Hartmut
A1  - Schlagel, D. L.
A1  - Lograsso, T. A.
A1  - Chollet, M.
A1  - Robert, A.
A1  - Sikorski, M.
A1  - Song, S.
A1  - Glownia, J. M.
A1  - Schuessler-Langeheine, Christian
A1  - Johnson, S. L.
A1  - Staub, U.
T1  - Itinerant and Localized Magnetization Dynamics in Antiferromagnetic Ho
JF  - Physical review letters
N2  - Using femtosecond time-resolved resonant magnetic x-ray diffraction at the Ho L-3 absorption edge, we investigate the demagnetization dynamics in antiferromagnetically ordered metallic Ho after femtosecond optical excitation. Tuning the x-ray energy to the electric dipole (E1, 2p -> 5d) or quadrupole (E2, 2p -> 4f) transition allows us to selectively and independently study the spin dynamics of the itinerant 5d and localized 4f electronic subsystems via the suppression of the magnetic (2 1 3-tau) satellite peak. We find demagnetization time scales very similar to ferromagnetic 4f systems, suggesting that the loss of magnetic order occurs via a similar spin-flip process in both cases. The simultaneous demagnetization of both subsystems demonstrates strong intra-atomic 4f-5d exchange coupling. In addition, an ultrafast lattice contraction due to the release of magneto-striction leads to a transient shift of the magnetic satellite peak.
Y1  - 2016
U6  - https://doi.org/10.1103/PhysRevLett.116.257202
SN  - 0031-9007
SN  - 1079-7114
VL  - 116
SP  - 6382
EP  - 6389
PB  - American Physical Society
CY  - College Park
ER  - 
TY  - JOUR
A1  - Siebrecht, R.
A1  - Schreyer, A.
A1  - Englisch, Uwe
A1  - Pietsch, Ullrich
A1  - Zabel, Hartmut
T1  - The new reflectometer ADAM at the ILL
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Thielemann-Kühn, Nele
A1  - Schick, Daniel
A1  - Pontius, Niko
A1  - Trabant, Christoph
A1  - Mitzner, Rolf
A1  - Holldack, Karsten
A1  - Zabel, Hartmut
A1  - Föhlisch, Alexander
A1  - Schuessler-Langeheine, Christian
T1  - Ultrafast and Energy-Efficient Quenching of Spin Order: Antiferromagnetism Beats Ferromagnetism
JF  - Physical review letters
N2  - By comparing femtosecond laser pulse induced ferro- and antiferromagnetic dynamics in one and the same material-metallic dysprosium-we show both to behave fundamentally different. Antiferromagnetic order is considerably faster and much more efficiently reduced by optical excitation than its ferromagnetic counterpart. We assign the fast and extremely efficient process in the antiferromagnet to an interatomic transfer of angular momentum within the spin system. Our findings imply that this angular momentum transfer channel is effective in other magnetic metals with nonparallel spin alignment. They also point out a possible route towards energy-efficient spin manipulation for magnetic devices.
Y1  - 2017
U6  - https://doi.org/10.1103/PhysRevLett.119.197202
SN  - 0031-9007
SN  - 1079-7114
VL  - 119
PB  - American Physical Society
CY  - College Park
ER  - 
TY  - JOUR
A1  - Pudell, Jan-Etienne
A1  - von Reppert, Alexander
A1  - Schick, D.
A1  - Zamponi, F.
A1  - Rössle, Matthias
A1  - Herzog, Marc
A1  - Zabel, Hartmut
A1  - Bargheer, Matias
T1  - Ultrafast negative thermal expansion driven by spin disorder
JF  - Physical review : B, Condensed matter and materials physics
N2  - We measure the transient strain profile in a nanoscale multilayer system composed of yttrium, holmium, and niobium after laser excitation using ultrafast x-ray diffraction. The strain propagation through each layer is determined by transient changes in the material-specific Bragg angles. We experimentally derive the exponentially decreasing stress profile driving the strain wave and show that it closely matches the optical penetration depth. Below the Neel temperature of Ho, the optical excitation triggers negative thermal expansion, which is induced by a quasi-instantaneous contractive stress and a second contractive stress contribution increasing on a 12-ps timescale. These two timescales were recently measured for the spin disordering in Ho [Rettig et al., Phys. Rev. Lett. 116, 257202 (2016)]. As a consequence, we observe an unconventional bipolar strain pulse with an inverted sign traveling through the heterostructure.
Y1  - 2019
U6  - https://doi.org/10.1103/PhysRevB.99.094304
SN  - 2469-9950
SN  - 2469-9969
VL  - 99
IS  - 9
PB  - American Physical Society
CY  - College Park
ER  -