Publications (22)
Temperature-dependent electron-phonon coupling in LaSrCuO probed by femtosecond X-ray diffraction
B. Mansart, M. J. G. Cottet, G. F. Mancini +16
The strength of the electron-phonon coupling parameter and its evolution throughout a solid's phase diagram often determines phenomena such as superconductivity, charge- and spin-d…
Femtosecond dynamics of the collinear-to-spiral antiferromagnetic phase transition in CuO
S. L. Johnson, R. A. de Souza, U. Staub +22
We report on the ultrafast dynamics of magnetic order in a single crystal of CuO at a temperature of 207 K in response to strong optical excitation using femtosecond resonant x-ray…
Identification of coherent lattice modulations coupled to charge and orbital order in a manganite
A. Caviezel, S. O. Mariager, S. L. Johnson +7
We apply grazing-incidence femtosecond x-ray diffraction to investigate the details of the atomic motion connected with a displacively excited coherent optical phonon. We concentra…
Ultrafast relaxation dynamics of the antiferrodistortive phase in Ca doped SrTiO3
M. Porer, M. Fechner, E. Bothschafter +19
The ultrafast dynamics of the octahedral rotation in Ca:SrTiO3 is studied by time resolved x-ray diffraction after photo excitation over the band gap. By monitoring the diffraction…
Watching the birth of a charge density wave order: diffraction study on nanometer-and picosecond-scales
C. Laulhé, T. Huber, G. Lantz +18
Femtosecond time-resolved X-ray diffraction is used to study a photo-induced phase transition between two charge density wave (CDW) states in 1T-TaS, namely the nearly commensu…
The photoinduced transition in magnetoresistive manganites: a comprehensive view
V. Esposito, L. Rettig, E. Abreu +12
We use femtosecond x-ray diffraction to study the structural response of charge and orbitally ordered PrCaMnO thin films across a phase transition induced by 800 nm…
Coherent Acoustic Perturbation of Second-Harmonic-Generation in NiO
L. Huber, A. Ferrer, T. Kubacka +14
We investigate the structural and magnetic origins of the unusual ultrafast second-harmonicgeneration (SHG) response of femtosecond-laser-excited nickel oxide (NiO) previously attr…
Direct observation of non-fully-symmetric coherent optical phonons by femtosecond x-ray diffraction
S. L. Johnson, P. Beaud, E. Möhr-Vorobeva +3
We directly measure by femtosecond time-resolved x-ray diffraction the E symmetry coherent phonon excited in bismuth by strong optical excitation. The magnitude of the E mo…
Domain size effects on the dynamics of a charge density wave in 1T-TaS2
G. Lantz, C. Laulhé, S. Ravy +11
Recent experiments have shown that the high temperature incommensurate (I) charge density wave (CDW) phase of 1T-TaS2 can be photoinduced from the lower temperature, nearly commens…
Ultrafast Laser-Induced Melting of Long-Range Magnetic Order in Multiferroic TbMnO3
Jeremy A. Johnson, T. Kubacka, M. C. Hoffmann +25
We performed ultrafast time-resolved near-infrared pump, resonant soft X-ray diffraction probe measurements to investigate the coupling between the photoexcited electronic system a…
Optical control of vibrational coherence triggered by an ultrafast phase transition
M. J. Neugebauer, T. Huber, M. Savoini +13
Femtosecond time-resolved x-ray diffraction is employed to study the dynamics of the periodic lattice distortion (PLD) associated with the charge-density-wave (CDW) in K0.3MoO3. Us…
Disentangling charge and structural contributions during coherent atomic motions studied by ultrafast resonant x-ray diffraction
L. Rettig, A. Caviezel, S. O. Mariager +20
We report on the ultrafast dynamics of charge order and structural response during the photoinduced suppression of charge and orbital order in a mixed-valence manganite. Employing…
Femtosecond phase-transition in hard x-ray excited bismuth
M. Makita, I. Vartiainen, I. Mohacs +19
The evolution of the bismuth crystal structure upon excitation of its A phonon has been intensely studied with short pulse optical lasers. Here we present the first-time obs…
Structural and magnetic dynamics of a laser induced phase transition in FeRh
S. O. Mariager, F. Pressacco, G. Ingold +11
We use time-resolved x-ray diffraction and magnetic optical Kerr effect to study the laser induced antiferromagnetic to ferromagnetic phase transition in FeRh. The structural respo…
Strain Wave Pathway to Semiconductor-to-Metal Transition revealed by time resolved X-ray powder diffraction
C. Mariette, M. Lorenc, H. Cailleau +42
Thanks to the remarkable developments of ultrafast science, one of today's challenges is to modify material state by controlling with a light pulse the coherent motions that connec…
Ultrafast structural dynamics of the Fe-pnictide parent compound BaFe2As2
L. Rettig, S. O. Mariager, A. Ferrer +8
Using femtosecond time-resolved x-ray diffraction we investigate the structural dynamics of the coherently excited A1g phonon mode in the Fe-pnictide parent compound BaFe2As2. The…
Coupling between a charge density wave and magnetism in an Heusler material
G. Lantz, M. J. Neugebauer, M. Kubli +10
The Prototypical magnetic memory shape alloy NiMnGa undergoes various phase transitions as a function of temperature, pressure, and doping. In the low-temperature phases below…
Nonlinear electron-phonon coupling in doped manganites
V. Esposito, R. Mankowsky, M. Fechner +9
We employ time-resolved resonant x-ray diffraction to study the melting of charge order and the associated insulator-metal transition in the doped manganite PrCaMnO…
Nonequilibrium Charge-Density-Wave Order Beyond the Thermal Limit
J. Maklar, Y. W. Windsor, C. W. Nicholson +17
The interaction of many-body systems with intense light pulses may lead to novel emergent phenomena far from equilibrium. Recent discoveries, such as the optical enhancement of the…
Structural and Magnetic Dynamics in the Magnetic Shape Memory Alloy NiMnGa
S. O. Mariager, C. Dornes, J. A. Johnson +11
Magnetic shape memory Heusler alloys are multiferroics stabilized by the correlations between electronic, magnetic and structural order. To study these correlations we use time res…
Ultrafast x-ray diffraction of a ferroelectric soft mode driven by broadband terahertz pulses
S. Grübel, J. A. Johnson, P. Beaud +14
Intense, few-cycle pulses in the terahertz frequency range have strong potential for schemes of control over vibrational modes in solid-state materials in the electronic ground-sta…
Coherent phonon dynamics at the martensitic phase transition of Ni_2MnGa
S. O. Mariager, A. Caviezel, P. Beaud +2
We use time-resolved optical reflectivity to study the laser stimulated dynamics in the magnetic shape memory alloy Ni_2MnGa. We observe two coherent optical phonons, at 1.2 THz in…