1. Evidence for a subtle structural symmetry breaking in EuB6
- Author
-
Martinho, H, Rettori, C, Dalpian, GM, Da Silva, JLF, Fisk, Z, and Oseroff, SB
- Abstract
This work presents a systematic Raman scattering study and first-principles calculations for the EuB6 system. Evidence for the presence of an incipient (∼1 × 10-4) tetragonal symmetry break of its crystalline structure was found. Forbidden Raman modes at ω fRm(1)∼1170cm-1, ω fRm(2)∼1400cm-1, and ωfRm(3)∼1500 cm-1 were observed. The tetragonal symmetry of ω fRm(2) and ωfRm(3) together with spin-polarized first-principles simulations of the structural and magnetic properties fully support such a break of symmetry. Our data and calculations explain the occurrence of ferromagnetism in Eu hexaborides, previously reported. © 2009 IOP Publishing Ltd.
- Published
- 2009