Lattice vibrations in KCuF3

Institute of Solid State Physics, Vienna University of Technology, 1040 Vienna, Austria; Institute of Applied Physics, Academy of Sciences of Moldova, 2028 Chişinău, Republic of Moldova
Annalen der Physik (Impact Factor: 1.51). 09/2011; 523(8‐9):645 - 651. DOI: 10.1002/andp.201100026

ABSTRACT We report on polarization dependent reflectivity measurements in KCuF3 in the far-infrared frequency regime. The observed IR active phonons at room temperature are in agreement with the expected modes for tetragonal symmetry. We observe a splitting of one mode already at 150 K and the appearance of a new mode in the vicinity of the Néel temperature.

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May 30, 2014