Coexistence of polar distortion and metallicity in PbTi1-xNbxO3

Abstract

Ferroelectricity has been believed unable to coexist with metallicity since the free carriers can screen the internal coulomb interactions of dipoles. Very recently, one kind of materials called as ferroelectric metal was reexamined. Here, we report the coexistence of metallicity and polar distortion in a new candidate for ferroelectric metal PbTi1-xNbxO3 via doping engineering. The ferroelectric-like polar distortion in all the doped PbTi1-xNbxO3, with x ranging from 0.04 to 0.12, was confirmed by the piezoresponse force microscopy and the scanning transmission electron microscopy measurements. PbTi1-xNbxO3 films become more conductive with more doping density, and emerge a metallic behavior when x reaches 0.12. Our first principle calculations further revealed that the doped Nb ions in the films can only provide free electrons, but not be able to damage the dipoles in unite cells even with the heaviest doping density of 0.12 due to their little impact on the off-centering of the Ti ions. We believe that these results confirm a feasibility of realizing the coexistence of metallicity and polar distortion for other ferroelectrics in a common way, and motivate the synthesis of some new materials with artificially designed properties even incompatible in nature.

References in corpus (5)

• Ferroelectric Instability under Screened Coulomb Interactions
• Local structural origins of the distinct electronic properties of Nb-substituted SrTiO${}_3$ and BaTi$O_3$
• Dual nature of the ferroelectric and metallic state in LiOsO${}_3$
• Metallic ferroelectricity induced by anisotropic unscreened coulomb interaction in LiOsO3
• Raman phonons in the ferroelectric-like metal LiOsO${}_3$

Cited by in corpus (9)

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• Effect of strain and doping on the polar metal phase in LiOsO${}_3$
• Quantum fluctuation of ferroelectric order in polar metals
• Observation of a Room Temperature Two-dimensional Ferroelectric Metal
• Two-dimensional metallic ferroelectricity in PbTe monolayer by electrostatic doping
• Magnetoresistance in Metallic Ferroelectrics