title: Magnetic field induced orbital polarization in cubic YbInNi4: determining the quartet ground state using x-ray linear dichroism.
abstract: We have been able to induce a linear dichroic signal in the Yb M(5) x-ray absorption white line of cubic YbInNi(4) by the application of a magnetic field. The nonzero integrated intensity of the magnetic field induced dichroic spectrum indicates a net noncubic 4f orbital polarization. A quantitative analysis of the temperature and field strength dependence establishes that the crystal-field ground state is a Γ(8) quartet. The results demonstrate the potential of magnetic field induced linear dichroism as a new powerful approach for the investigation of the degeneracy and orbital degrees of freedom of cubic heavy-fermion and Kondo systems.
authors.affiliation: Institute of Physics II, University of Cologne, Zülpicher Strasse 77, D-50937 Cologne, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Willers
authors.forename: J C
authors.initials: JC
authors.lastname: Cezar
authors.forename: N B
authors.initials: NB
authors.lastname: Brookes
authors.forename: Z
authors.initials: Z
authors.lastname: Hu
authors.forename: F
authors.initials: F
authors.lastname: Strigari
authors.forename: P
authors.initials: P
authors.lastname: Körner
authors.forename: N
authors.initials: N
authors.lastname: Hollmann
authors.forename: D
authors.initials: D
authors.lastname: Schmitz
authors.forename: A
authors.initials: A
authors.lastname: Bianchi
authors.forename: Z
authors.initials: Z
authors.lastname: Fisk
authors.forename: A
authors.initials: A
authors.lastname: Tanaka
authors.forename: L H
authors.initials: LH
authors.lastname: Tjeng
authors.forename: A
authors.initials: A
authors.lastname: Severing