Detail publikace

Antiferrodistortive phase transition in EuTiO3

GOIAN, V. KAMBA, S. PACHEROVÁ, O. DRAHOKOUPIL, J. PALATINUS, L. DUŠEK, M. ROHLÍČEK, J. SAVINOV, M. LAUFEK, F. SCHRANZ, W. FUITH, A. KACHLÍK, M. MACA, K. SHKABKO, A. SAGARNA, L. WEIDENKAFF, A. BELIK, A.

Originální název

Antiferrodistortive phase transition in EuTiO3

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

angličtina

Originální abstrakt

X-ray diffraction, dynamical mechanical analysis, and infrared reflectivity studies revealed an antiferrodistortive phase transition in EuTiO3 ceramics. Near 300 K, the perovskite structure changes from cubic Pm3m to tetragonal I4/mcm due to antiphase tilting of oxygen octahedra along the c axis. The phase transition is analogous to SrTiO3. However, some ceramics as well as single crystals of EuTiO3 show different infrared reflectivity spectra bringing evidence of a different crystal structure. In such samples, electron diffraction revealed an incommensurate tetragonal structure with modulation wave vector q =0.38 a. Extra phonons in samples with modulated structure are activated in the IR spectra due to folding of the Brillouin zone. We propose that defects such as Eu3+ and oxygen vacancies strongly influence the temperature of the phase transition to antiferrodistortive phase as well as the tendency to incommensurate modulation in EuTiO3.

Klíčová slova

EuTiO3; phase transition; X-ray diffraction; infrared reflectivity

Autoři

GOIAN, V.; KAMBA, S.; PACHEROVÁ, O.; DRAHOKOUPIL, J.; PALATINUS, L.; DUŠEK, M.; ROHLÍČEK, J.; SAVINOV, M.; LAUFEK, F.; SCHRANZ, W.; FUITH, A.; KACHLÍK, M.; MACA, K.; SHKABKO, A.; SAGARNA, L.; WEIDENKAFF, A.; BELIK, A.

Rok RIV

2012

Vydáno

25. 8. 2012

Nakladatel

AMER PHYSICAL SOC

Místo

ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844

ISSN

1098-0121

Periodikum

PHYSICAL REVIEW B

Ročník

86

Číslo

054112

Stát

Spojené státy americké

Strany od

054112-1

Strany do

054112-9

Strany počet

9