TY  - JOUR
A1  - Bojahr, Andre
A1  - Herzog, Marc
A1  - Schick, Daniel
A1  - Vrejoiu, Ionela
A1  - Bargheer, Matias
T1  - Calibrated real-time detection of nonlinearly propagating strain waves
T2  - Physical review : B, Condensed matter and materials physics
N2  - Epitaxially grown metallic oxide transducers support the generation of ultrashort strain pulses in SrTiO3 (STO) with high amplitudes up to 0.5%. The strain amplitudes are calibrated by real-time measurements of the lattice deformation using ultrafast x-ray diffraction. We determine the speed at which the strain fronts propagate by broadband picosecond ultrasonics and conclude that, above a strain level of approx. 0.2%, the compressive and tensile strain components travel at considerably different sound velocities, indicating nonlinear wave behavior. Simulations based on an anharmonic linear-chain model are in excellent accord with the experimental findings and show how the spectrum of coherent phonon modes changes with time.
Y1  - 2012
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/35574
SN  - 1098-0121
VL  - 86
IS  - 14
PB  - American Physical Society
CY  - College Park
ER  -