title: Tunable Charge and Spin Order in PrNiO_{3} Thin Films and Superlattices.
abstract: We use polarized Raman scattering to probe lattice vibrations and charge ordering in 12 nm thick, epitaxially strained PrNiO_{3} films, and in superlattices of PrNiO_{3} with the band insulator PrAlO_{3}. A carefully adjusted confocal geometry is used to eliminate the substrate contribution to the Raman spectra. In films and superlattices under tensile strain which undergo a metal-insulator transition upon cooling, the Raman spectra reveal phonon modes characteristic of charge ordering. These anomalous phonons do not appear in compressively strained films, which remain metallic at all temperatures. For superlattices under compressive strain, the Raman spectra show no evidence of anomalous phonons indicative of charge ordering, while complementary resonant x-ray scattering experiments reveal antiferromagnetic order associated with a modest increase in resistivity upon cooling. This confirms theoretical predictions of a spin density wave phase driven by spatial confinement of the conduction electrons.
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Hepting
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Minola
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany and Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen-Campus BESSY II, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Frano
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Cristiani
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Logvenov
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen-Campus BESSY II, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Schierle
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Wu
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany and Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen-Campus BESSY II, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Bluschke
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen-Campus BESSY II, Albert-Einstein-Strasse 15, D-12489 Berlin, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Weschke
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: H-U
authors.initials: HU
authors.lastname: Habermeier
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Benckiser
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Le Tacon
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Keimer