Berlin 2015 – wissenschaftliches Programm
DF 5.21: Poster
Montag, 16. März 2015, 19:00–21:00, Poster C
Investigation of low-frequency Raman modes in BiFeO3 epitaxial thin films with respect to azimuthal orientation — •Andreas Talkenberger1, Cameliu Himcinschi1, Christian Röder1, Ionela Vrejoiu2,3, Florian Johann2, and Jens Kortus1 — 1TU Bergakademie Freiberg, Institute of Theoretical Physics, Leipziger Str. 23, D-09596 Freiberg — 2Max Planck Institute of Microstructure Physics, Weinberg 2, D-06120 Halle — 3Max Planck Institute for Solid State Research, Heisenbergstr. 1, D-70569 Stuttgart
In this work we present results of highly accurate Raman spectroscopic experiments applied in azimuthal rotation measurements on epitaxial BiFeO3 thin films grown on different scandate substrates. We observe periodic changes in Raman position, full width at half maximum and intensity for some phonon modes as a function of the azimuthal angle Φ. Further analysis revealed the possibility of the so far controversial assignment of Raman modes at low frequencies (< 250 cm−1) through rotational Raman measurements, that show high sensitivity towards the mentioned parameters. We successfully simulated the azimuthal behaviour of Raman intensity and position of selected modes offering a symmetry assignment for them. In addition our results support the domain character of the BFO/DSO thin film identified by piezoresponse-force microscopy measurements.
This work is supported by the German Research Foundation DFG HI 1534/1-2.