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arXiv · 2008.01460

Symmetry breaking in single crystal SrTiO$_3$ plates: EPR manifestations

Bulat F. Gabbasov·Irina N. Gracheva·Alexander A. Rodionov·Sergey I. Nikitin·Dmitry G. Zverev·Vladimir A. Trepakov·Alexandr Dejneka·Lubomir Jastrabik·Roman V. Yusupov
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Abstract

Electron paramagnetic resonance studies of the impurity Fe$^{3+}$ and Mn$^{4+}$ centers indicate that the symmetry of the crystal structure of millimeter-scale strontium titanate plates above 105 K lowers in the bulk from cubic to tetragonal, different from that of the conventional low-temperature antiferrodistortive phase. It is shown that the effect does not originate from the residual stress; its magnitude (observed tetragonal distortion) and particular manifestations depend on plate orientation, surface quality and the geometry of a sample. Peculiarities of the observed phenomenon are presented and possible scenario of its realization is discussed.

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Bulat F. Gabbasov, Irina N. Gracheva, Alexander A. Rodionov, Sergey I. Nikitin, Dmitry G. Zverev, Vladimir A. Trepakov, Alexandr Dejneka, Lubomir Jastrabik, Roman V. Yusupov. 2020-08-04. Symmetry breaking in single crystal SrTiO$_3$ plates: EPR manifestations. https://doi.org/10.1209/0295-5075/133/37002

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