Phonon metamorphosis in ferromagnetic manganite films: Probing the evolution of an inhomogeneous state

  title={Phonon metamorphosis in ferromagnetic manganite films: Probing the evolution of an inhomogeneous state},
  author={Ch. Hartinger and Franz Mayr and Alois Loidl and Thilo Kopp},
  journal={Physical Review B},
The analysis of phonon anomalies provides valuable information about the cooperative dynamics of lattice, spin and charge degrees of freedom. Significant is the anomalous temperature dependence of the external modes observed in La$_{2/3}$Sr$_{1/3}$MnO$_{3}$ (LSMO) films. The two external modes merge close to the ferromagnetic to paramagnetic transition at $T_C$ and, moreover, two new modes evolve in this temperature range with strong resonances at slightly higher frequencies. We propose that… 
Low-Energy Excitations in La1.2Sr1.8Mn2O7 Investigated by Ellipsometry
The low-energy excitations of the bilayered manganite La{sub 1.2}Sr{sub 1.8}Mn{sub 2}O{sub 7} have been explored by spectral ellipsometry from two faces of a single crystal over the range from 0.006
Temperature dependence of phonons spectra and allied properties of rhombohedral La0.7Sr0.3MnO3 are investigated by using the lattice dynamical method. A tendency of phonon mode to instability causing
Polaronic excitations in colossal magnetoresistance manganite films
In the colossal magnetoresistance manganites polarons have been proposed as the charge carrier state which localizes across the metal-insulator transition. The character of the polarons is still
Novel aspects of charge and lattice dynamics in the hole-doped manganite La0.67Sr0.33MnO3
Previous infrared studies on the hole-doped manganite La0.67Sr0.33MnO3 (LSMO) have analysed its charge dynamics in terms of one type of charge carrier despite evidence of both electron and hole Fermi
Dynamic conductivity from audio to optical frequencies of semiconducting manganites approaching the metal‐insulator transition
We report the frequency‐dependent conductivity of the manganite system La1‐xSrxMnO3 (x≤0.2) when approaching the metal‐insulator transition from the insulating side. Results from low‐frequency
Infrared Spectroscopy and Nano-Imaging of La0.67Sr0.33Mno3 Films
  • P. Xu
  • Physics, Materials Science
  • 2017
Charge transport properties of manganites can be significantly modified by temperature, chemical doping, strain, and interfacial boundaries. In this dissertation, we report studies on broadband
Magnetic properties of La0.7Sr0.3MnO3 nanopowders
The peculiarities of the magnetization of a nanopowder (particle size 12nm) of the manganite La0.7Sr0.3MnO3 are investigated. It is shown that for temperatures below the Curie point the magnetization
TOPICAL REVIEW: Rare region effects at classical, quantum and nonequilibrium phase transitions
Rare regions, i.e., rare large spatial disorder fluctuations, can dramatically change the properties of a phase transition in a quenched disordered system. In generic classical equilibrium systems,


Cooperative dynamics in doped manganite films: Phonon anomalies in the ferromagnetic state
We present optical measurements of phononic excitations in La$_{2/3}$Ca$_{1/3}$MnO$_{3}$ (LCMO) and La$_{2/3}$Sr$_{1/3}$MnO$_{3}$ (LSMO) thin films covering the full temperature range from the
Griffiths singularities and magnetoresistive manganites
The large, so-called colossal magnetoresistivity of doped LaMnO 3 has attracted considerable attention, but is only one unusual feature of the ferromagnetic transition in these compounds. We examine
Spatially Inhomogeneous Metal-Insulator Transition in Doped Manganites.
The results suggest that the transition and the associated magnetoresistance behavior should be viewed as a percolation of metallic ferromagnetic domains.
Percolative phase separation underlies colossal magnetoresistance in mixed-valent manganites
Colossal magnetoresistance—an unusually large change of resistivity observed in certain materials following application of magnetic field—has been extensively researched in ferromagnetic perovskite
Comparative study of optical phonons in the rhombohedrally distorted perovskites LaAlO 3 and LaMnO 3
The Raman and infrared phonons of isostructural rhombohedral LaMnO3 and LaAlO3 are studied at room temperature. The experimental spectra are compared with the prediction of lattice-dynamical
Observation of two time scales in the ferromagnetic manganite La1-xCaxMnO3, x approximately 0.3.
We report new zero-field muon spin relaxation and neutron spin echo measurements in ferromagnetic (FM) (La,Ca)MnO3 which suggest at least two spatially separated regions possessing very different
Phase separation scenario for manganese oxides and related materials
Experimental data reviewed here by applying several techniques for manganites and other materials are consistent with a transition between the antiferromagnetic insulator state of the hole-undoped limit and the ferromagnetic metal at finite hole density through a mixed-phase process.
Intrinsic inhomogeneities in manganite thin films investigated with scanning tunneling spectroscopy.
Thin films of La0.7Sr0.3MnO3 on MgO show a metal insulator transition and colossal magnetoresistance that can be explained by intrinsic spatial inhomogeneities and undergo a percolation transition.