Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 43: Correlated Electrons: Heavy Fermions 2
TT 43.9: Vortrag
Donnerstag, 26. März 2009, 18:00–18:15, HSZ 301
Investigation of the crystal-field ground state of YbInNi4 with polarization dependent Yb-M-edge x ray absorption spectroscopy. — Peter Körner1, •Andrea Severing1, Thomas Willers1, Zhiwei Hu1, Nils Hollmann1, Detlef Schmitz2, Zachary Fisk3, Andrea Bianchi3, and Liu Hao Tjeng1 — 1Institute of Physics II, University of Cologne — 2BESSY Berlin — 3University of California, Irvine, USA
YbInNi4 serves as a stable valent reference sample for YbInCu4 which undergoes a first order valence transition as function of temperature. Although intensively studied in the past, the crystal-field ground state of YbInNi4 remained a matter of debate [1-4]. We will present our investigations of the crystal-field ground state of YbInNi4 with soft-x-ray absorption spectroscopy at the Yb-M-edge. Soft-x-ray absorption spectroscopy is sensitive to the symmetry of the initial state and through the polarization dependence direct spectroscopic information about the |Jz⟩ admixtures of the ground state [5] can be obtained. However, since YbInNi4 is cubic, a polarization effect can only arise when a magnetic field is applied to split up the crystal-field states. We will show that the induced linear dichroism allows to distinguish between the various ground state possibilities.
[1] A. Severing et al., Physica B 163, 409 (1990).
[2] J.L. Sarrao et al., Phys. Rev. B 57, 7785 (1998).
[3] P.G. Pagiuso et al., Phys. Rev. B 63, 144430 (2001).
[4] T. Park et al. Phys. Rev. Lett. 96, 046405 (2006).
[5] P. Hansmann et al. , Phys. Rev. Lett. 100, 066405 (2008).