title: Direct characterization of photoinduced lattice dynamics in BaFe2As2.
abstract: Ultrafast light pulses can modify electronic properties of quantum materials by perturbing the underlying, intertwined degrees of freedom. In particular, iron-based superconductors exhibit a strong coupling among electronic nematic fluctuations, spins and the lattice, serving as a playground for ultrafast manipulation. Here we use time-resolved X-ray scattering to measure the lattice dynamics of photoexcited BaFe2As2. On optical excitation, no signature of an ultrafast change of the crystal symmetry is observed, but the lattice oscillates rapidly in time due to the coherent excitation of an A1g mode that modulates the Fe-As-Fe bond angle. We directly quantify the coherent lattice dynamics and show that even a small photoinduced lattice distortion can induce notable changes in the electronic and magnetic properties. Our analysis implies that transient structural modification can be an effective tool for manipulating the electronic properties of multi-orbital systems, where electronic instabilities are sensitive to the orbital character of bands.
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: S
authors.initials: S
authors.lastname: Gerber
authors.affiliation: Department of Physics, Chungbuk National University, 52 Naesudong-ro, Heungdeok-gu, Cheongju 361-763, Korea.
authors.forename: K W
authors.initials: KW
authors.lastname: Kim
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: D
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Departments of Physics and Applied Physics, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA.
authors.forename: N
authors.initials: N
authors.lastname: Plonka
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Departments of Physics and Applied Physics, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA.
authors.forename: M
authors.initials: M
authors.lastname: Yi
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: G L
authors.initials: GL
authors.lastname: Dakovski
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: D
authors.initials: D
authors.lastname: Leuenberger
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: P S
authors.initials: PS
authors.lastname: Kirchmann
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: R G
authors.initials: RG
authors.lastname: Moore
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: M
authors.initials: M
authors.lastname: Chollet
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Glownia
authors.affiliation: Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: J-S
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: A
authors.initials: A
authors.lastname: Mehta
authors.affiliation: Computational Research Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: A F
authors.initials: AF
authors.lastname: Kemper
authors.affiliation: Institute for Solid State Physics, Karlsruhe Institute of Technology, Hermann-v.-Helmholtz-Platz 1, 76021 Karlsruhe, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Wolf
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Y-D
authors.initials: YD
authors.lastname: Chuang
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Hussain
authors.affiliation: SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: C-C
authors.initials: CC
authors.lastname: Kao
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: B
authors.identifier: http://orcid.org/0000-0002-3747-8484
authors.initials: B
authors.lastname: Moritz
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.|Departments of Physics and Applied Physics, Stanford University, 476 Lomita Mall, Stanford, California 94305, USA.
authors.forename: Z-X
authors.initials: ZX
authors.lastname: Shen
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: T P
authors.initials: TP
authors.lastname: Devereaux
authors.affiliation: Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory and Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: W-S
authors.initials: WS
authors.lastname: Lee