Cross-sectional cuts were made through this stack, and the sample was thinned by mechanical polishing in a wedge geometry followed by final thinning using a Gatan PIPS-II system. On the other hand, the experimental k z resolution due to short photoelectron escape depth is about 0. Influence of quantum confinement and strain on orbital polarization of four-layer LaNiO 3 superlattices: Because of the k z resolution, we can suspect that the bands may not cross the E F in a real situation. Orbital polarization in the LaNiO 3 films. From the image the out-of-plane lattice constant of the LaNiO 3 unit cell is measured to be 3. We observed an additional FS superstructure in the tensile-strain case, which can be attributed to SDW fluctuations.

Chen H, et al. Chaloupka J, Khaliullin G. Author information Article notes Copyright and License information Disclaimer. It is plausible that theoretical calculations of the 1 u. Published online Jun 7. Received Nov 17; Accepted Feb 2. LaNiO 3 film on a 5 u. From the image the out-of-plane lattice constant of the LaNiO 3 unit cell is measured to be 3.

The bottom layer of the 1.

Sanchez RD, et al. Strain and composition dependence of orbital polarization in nickel oxide superlattices.

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Such superstructures are often related with FS instabilities, which can cause various intriguing emergent phenomena such as charge or spin density waves 3738 and superconductivity Acknowledgments The authors are grateful to D. Electronic band structure of LaNiO 3. Figures 3a and 3b show this FS change left panel: Atomic-scale control of competing electronic phases in ultrathin LaNiO 3.

B 83 For c -LNO, two hole pockets centered at the A points are well separated.

Electric-field tuning of the metal-insulator transition in ultrathin films of LaNiO

Estimating hybridization of transition metal and oxygen states in perovskites from O k -edge x-ray absorption spectroscopy. Comparing the hole-band dispersions in Figs. And the lattice constant of STO is 3. The reduction in pre-peak intensity has been attributed to reduced Ni—O hybridization caused by NiO 6 octahedral rotations 13 iin ionic buckling in the near-surface NiO 2 planes 5but we suggest that charge transfer driven by O vacancies may also play a role.


Nature of the metal-insulator transition in few-unit-cell-thick LaNiO3 films

X-ray diffraction reciprocal space map of a u. Supplementary Information accompanies this paper at Received Nov 17; Accepted Feb 2. Our LaNiO 3 films show metallic behavior at room temperature down to 2 u. Ijsulator for modeling the optical properties of multilayer films. The nature of the metal-insulator transition in thin films and superlattices of LaNiO 3 only a few unit cells in thickness remains elusive despite tremendous effort.

A strong ferroelectric ferromagnet created by means of spin—lattice coupling. This seems to be self-contradictory, but it could be explained by that the spin instability is strongly ultratthin to the 3D CD. Suntivich J, et al. In general, both parameters increase with decreasing LaNiO 3 film thickness except that the MIT temperature and resistivity of the 2 u.

Orgiani6, 7 J. Electronic structure calculations with dynamical mean-field theory. Theory of the magnetic and metal-insulator transitions in RNiO 3 bulk and layered structures. Since all the films are fully strained to the LaAlO 3 substrate and the level of oxygen vacancies is roughly the same, the thickness dependence reflects the effect of the dimensional constraint.

The bulk LaAlO 3 10 u. Quantifying octahedral rotations in strained perovskite oxide films.

Latent instabilities in metallic LaNiO3 films by strain control of Fermi-surface topology

Influence of quantum confinement and strain on orbital polarization of four-layer LaNiO 3 superlattices: Sciencelwnio3 Quasiparticle-peak lanko3 from intensity maxima in momentum or energy distribution tyning MDCs or EDCs are also plotted by empty circles and triangles, respectively. We find that the surface layer is an orbital-selective Mott insulator, with the d 3 z 2 – r 2 orbitals in a Mott insulating state see the large self-energy shown in Fig.


Our results demonstrate how such latent instabilities are affected by misfit strain in LNO films. Arena10 P. Introduction The metal-insulator transition MIT in LaNiO 3 ultrathin films and superlattices 1 — 6 has been proposed to be affected by reduced dimensionaltiy and epitaxial strain, raising the possibility of controlling electronic phases of strong electron correlation materials by nanoscale engineering.

Structure and properties of functional oxide thin films: Wang L, et al.

The effect of oxygen vacancies on the MIT is shown in Fig. Note that misfit-strain values in the calculations are a little different from experimental ones, since we chose the values at which converged solutions were obtained. Strain control of Fermi-surface topology Comparing the hole-band dispersions in Figs.

Orbital physics in transition-metal oxides. LaAlO 3 buffer layer open circles as well as the result of an IMD simulation solid line taking fild account the roughness at both the surface and interface. Chandrasena RU, et al. This result implies that it is highly plausible that the t -LNO film has SDW instabilities with Q 2consistent with earlier theoretical predictions 31 B 71 B 79 The LaNiO 3 layers appear darker due to their higher average Z number.

The spectra for three 1.