Ultrafast dynamics of phase transitions; Femtosecond x-ray diffraction; Ultrafast phenomena in solid matter; manganites; ultrafast phenomena
P. Beaud, A. Caviezel, et al. (2014), A time-dependent order parameter for ultrafast photoinduced phase transitions, in Nature Materials
Johnson S. L., Beaud P., Moehr-Vorobeva E., Caviezel A., Ingold G., Milne C. J. (2013), Direct observation of non-fully-symmetric coherent optical phonons by femtosecond x-ray diffraction, in PHYSICAL REVIEW B
, 87(5), 054301-1-054301-8.
Caviezel A., Mariager S. O., Johnson S. L., Moehr-Vorobeva E., Huang S. W., Ingold G., Staub U., Milne C. J., Cheong S. -W., Beaud P. (2013), Identification of coherent lattice modulations coupled to charge and orbital order in a manganite, in PHYSICAL REVIEW B
, 87(20), 205104-1-205104-6.
Caviezel A., Staub U., Johnson S. L., Mariager S. O., Ingold G., Moehr-Vorobeva E., Garganourakis M., Huang S.-W., Milne C. J., Jia Q. X., Chepng S.-W., Beaud P. (2013), Optical and x-ray time resolved study of the structural transition in mixed valence manganites, in XVIIIth International Conference on Ultrafast Phenomena
Mariager S. O., Caviezel A., Beaud P., Quitmann C., Ingold G. (2012), Coherent phonon dynamics at the martensitic phase transition of Ni2MnGa, in APPLIED PHYSICS LETTERS
, 100(26), 261911-1-261911-4.
Johnson SL, de Souza RA, Staub U, Beaud P, Mohr-Vorobeva E, Ingold G, Caviezel A, Scagnoli V, Schlotter WF, Turner JJ, Krupin O, Lee WS, Chuang YD, Patthey L, Moore RG, Lu D, Yi M, Kirchmann PS, Trigo M, Denes P, Doering D, Hussain Z, Shen ZX, Prabhakaran D, Boothroyd AT (2012), Femtosecond Dynamics of the Collinear-to-Spiral Antiferromagnetic Phase Transition in CuO, in PHYSICAL REVIEW LETTERS
, 108(3), 037203-1-037203-5.
Caviezel A., Staub U., Johnson S. L., Mariager S. O., Moehr-Vorobeva E., Ingold G., Milne C. J., Garganourakis M., Scagnoli V., Huang S. W., Jia Q. X., Cheong S. -W., Beaud P. (2012), Femtosecond dynamics of the structural transition in mixed valence manganites, in PHYSICAL REVIEW B
, 86(17), 174105-1-174105-8.
Mariager SO, Pressacco F, Ingold G, Caviezel A, Mohr-Vorobeva E, Beaud P, Johnson SL, Milne CJ, Mancini E, Moyerman S, Fullerton EE, Feidenhans'l R, Back CH, Quitmann C (2012), Structural and Magnetic Dynamics of a Laser Induced Phase Transition in FeRh, in PHYSICAL REVIEW LETTERS
, 108(8), 087201-1-087201-5.
Beaud P, Johnson SL, Vorobeva E, Milne CJ, Caviezel A, Mariager SO, De Souza RA, Staub U, Ingold G (2011), Ultrafast Structural Dynamics in Condensed Matter, in CHIMIA
, 65(5), 308-312.
The proposed research will advance our current understanding of the interplay of the electronic system with the lattice in strongly correlated electron systems. In many such solids there are strong coupling mechanisms between the electronic and lattice energy subsystems, often resulting in a subtle balance between opposing forces. Femtosecond x-ray diffraction is a unique tool that provides unambiguous, quantitative structural information on time scales relevant for the lattice dynamics of these systems. Our proposed studies will focus on several related manganite compounds. We intend to measure in the same systems both the structural dynamics using femtosecond x-ray diffraction and the static electronic ordering using resonant diffraction. The ultimate goal of our studies at the SLS is to combine these efforts towards a time-resolved resonant x-ray diffraction experiment at the FLASH soft x-ray FEL and at future hard x-ray FELs to reveal correlated structural and electronic dynamics as they develop. In the present proposal we ask for funding of a PhD student. He or she will study the proposed manganites over a wide parameter range with ultrafast optical methods and will study selected samples together with the FEMTO team with femtosecond x-ray diffraction. The FEMTO-project at the Swiss Light Source (SLS) is currently the only operational tunable source delivering femtosecond hard x-rays tunable in the energy range from 5 to 12 keV with a well-collimated beam. The proposed diffraction experiments in the hard x-ray range cannot be performed today at any other facility worldwide.