Cubic lead perovskite PbMoO3 with anomalous metallic behavior

Abstract

A previously unreported Pb-based perovskite PbMoO${}_3$ is obtained by high-pressure and high-temperature synthesis. This material crystallizes in the $Pm\bar{3}m$ cubic structure at room temperature, making it distinct from typical Pb-based perovskite oxides with a structural distortion. PbMoO${}_3$ exhibits a metallic behavior down to 0.1 K with an unusual $T$-sub linear dependence of the electrical resistivity. Moreover, a large specific heat is observed at low temperatures accompanied by a peak in $C_P/T^3$ around 10 K, in marked contrast to the isostructural metallic system SrMoO${}_3$. These transport and thermal properties for PbMoO${}_3$, taking into account anomalously large Pb atomic displacements detected through diffraction experiments, are attributed to a low-energy vibrational mode, associated with incoherent off-centering of lone pair Pb${}^{2+}$ cations. We discuss the unusual behavior of the electrical resistivity in terms of a polaron-like conduction, mediated by the strong coupling between conduction electrons and optical phonons of the local low-energy vibrational mode.

arXiv comment5 pages, 5 figures

References in corpus (8)

• A ferroelectric-like structural transition in a metal
• On the Fermi Liquid to Polaron Crossover I: General Results
• Neutron Diffuse Scattering from Polar Nanoregions in the Relaxor Pb(Mg1/3Nb2/3)O3
• Odd-parity superconductivity in the vicinity of inversion symmetry breaking in spin-orbit-coupled systems
• Metallic "Ferroelectricity" in the Pyrochlore Cd2Re2O7
• Critical enhancement of thermopower in a chemically tuned polar semimetal MoTe${}_2$
• Large Low Temperature Specific Heat in Pyrochlore Bi${}_2$Ti${}_2$O${}_7$
• Metal-Insulator Transition and Orbital Order in PbRuO3

Cited by in corpus (3)

• Crystal Graph Convolutional Neural Networks for an Accurate and Interpretable Prediction of Material Properties
• First-principles study of the electronic, magnetic, and crystal structure of perovskite molybdates
• Low-temperature transport in high-conductivity correlated metals: a density-functional plus dynamical mean-field study of cubic perovskites