Regensburg 2007 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 14: Spin Systems and Itinerant Magnets
TT 14.10: Vortrag
Dienstag, 27. März 2007, 16:45–17:00, H19
Study of magnetic ordering in YTi03 using high-resolution dilatometry — •William Knafo1,2, Christoph Meingast1, Alexander Boris3, Paul Popovich3, Natalia Kovaleva3, Petar Yordanov3, Andrei Maljuk3, Bernhard Keimer3, and Hilbert v. Löhneysen1,2 — 1Forschungszentrum Karlsruhe, Institut für Festkörperphysik, D-76021 Karlsruhe — 2Physikalisches Institut, Universität Karlsruhe, D-76128 Karlsruhe — 3Max-Planck-Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart
The perovskite YTi03 orders ferromagnetically below TC = 26.7 K, whereas LaTiO3 orders antiferromagnetically below TN = 150 K. The origin of this difference is currently being strongly debated and is related to the different types of lattice distortions, e.g. to the GdFe03-type distortion and to the Jahn-Teller distortion induced by the orbital ordering in these systems [1-5]. We present here a study of the macroscopic distortions associated with magnetic ordering in YTi03 using thermal expansion and magnetostriction measurements. The uniaxial pressure dependencies of the Curie temperature TC and of the low temperature ferromagnetic moment are extracted from our data. The coupling of magnetism to the different kinds of distortion (i.e. of GdFe03- and Jahn-Teller-type) will be discussed.
[1] Ulrich et al., Phys. Rev. Lett. 89, 167202, (2002).
[2] Iga et al., Phys. Rev. Lett. 92, 176403, (2004).
[3] Akimitsu et al., J. Phys. Soc. Jpn. 70, 3475 (2001).
[4] Pavarini et al., New J. Phys. 7, 188 (2005).
[5] Mochizuki and Imada, New J. Phys. 6, 154 (2004).