Breakdown of the lattice polaron picture in La0.7Ca0.3MnO3 single crystals

Abstract

When heated through the magnetic transition at Tc, La0.7Ca0.3MnO3 changes from a band metal to a polaronic insulator. The Hall constant R_H, through its activated behavior and sign anomaly, provides key evidence for polaronic behavior. We use R_H and the Hall mobility to demonstrate the breakdown of the polaron phase. Above 1.4Tc, the polaron picture holds in detail, while below, the activation energies of both R_H and the mobility deviate strongly from their polaronic values. These changes reflect the presence of metallic, ferromagnetic fluctuations, in the volume of which the Hall effect develops additional contributions tied to quantal phases.

11 pages, 3 figures, final version to appear in Phys. Rev. B Rapid

References in corpus (1)

• Magnetotransport in manganites and the role of quantal phases II: Experiment

Cited by in corpus (12)

• Charge Transport in Manganites: Hopping Conduction, the Anomalous Hall Effect and Universal Scaling
• A 'p-n' diode with hole and electron-doped lanthanum manganite
• Nanometer-sized Regions of Charge Ordering and Charge Melting in La2/3Ca1/3MnO3 Revealed by Electron Micro-diffraction
• Low-energy charge dynamics in La${}_{\text{0.7}}$Ca${}_{\text{0.3}}$MnO${}_{\text{3}}$: THz time-domain spectroscopic studies
• Reentrant spin glass behavior in a layered manganite La1.2Sr1.8Mn2O7 single crystals
• Dynamical mean-field theory of a double-exchange model with diagonal disorder
• Berry's phase contribution to the anomalous Hall effect of gadolinium
• Extrinsic inhomogeneity effects in magnetic, transport and magnetoresistive properties of La_{1-x}Ca_{x}MnO_{3} (x\approx 0.33) crystal prepared by the floating zone method
• Polaronic signature in the metallic phase of La0.7Ca0.3MnO3 films detected by scanning tunneling spectroscopy
• Anomalous Hall Effect of Reentrant Spin Glass System Fe1-xAlx (x ~ 0.3)
• Enhancement of the anomalous Hall effect and spin glass behavior in the bilayered manganite La(2-2x)Sr(1+2x)Mn2O7
• Signatures of electronic phase separation in the Hall effect of anisotropically strained La0.67Ca0.33MnO3 films