The Anderson-Mott transition induced by hole-doping in Nd1-xTiO3

Abstract

The insulator/metal transition induced by hole-doping due to neodymium vacancies of the Mott- Hubbard antiferromagnetic insulator, Nd1-xTiO3, is studied over the composition range 0.010(6) < x < 0.243(10). Insulating p-types conduction is found for x < 0.071(10). Anderson localization in the presence of a Mott-Hubbard gap, is the dominant localization mechanism for the range of 0.074(10) < x < 0.089(1) samples. For x < 0.089(1), n-type conduction is observed and the activation energy extrapolates to zero by x < 0.1. The 0.095(8) < x < 0.203(10) samples are Fermi-liquid metals and the effects of strong electronic correlations are evident near the metal-to-insulator boundaries in features such as large Fermi liquid T2 coefficients. For 0.074(9) < x < 0.112(4), a weak negative magnetoresistance is found below ~ 15 K and it is attributed to the interaction of conduction electrons with Nd3+ magnetic moments. Combining information from our companion study of the magnetic properties of Nd1-xTiO3 solid solution, a phase diagram is proposed. The main conclusions are that long range antiferromagnetic order disappears before the onset of metallic behavior and that the Anderson-Mott transition occurs over a finite range of doping levels. Our results differ from conclusions drawn from a similar study on the hole doped Nd1-xCaxTiO3 system which found the co-existence of antiferromagnetic order and metallic behavior and that the Mott transition occurs at a discrete doping level.

References in corpus (4)

• The ground state of heavily-overdoped non-superconducting La${}_{2-x}$Sr${}_x$CuO${}_4$
• Charge Stripes and Antiferromagnetism in Insulating Nickelates and Superconducting Cuprates
• The metal-insulator transition in amorphous Si_{1-x}Ni_x: Evidence for Mott's minimum metallic conductivity
• The effect of hole-doping on the magnetic properties of Nd1-xTiO3

Cited by in corpus (8)

• Phase separation in doped Mott insulators
• A New Line Defect in NdTiO3 Perovskite
• Metal-Insulator-Transition in a Weakly interacting Disordered Electron System
• The onset of magnetism peaked around x=1/4 in optimally electron-doped LnFe(1-x)Ru(x)AsO(1-y)F(y) (Ln = La, Nd or Sm) superconductors
• A local theory for Mott-Anderson localization
• From Weak Antilocalization to Kondo Scattering in a Magnetic Complex Oxide Interface
• Response of the lattice across the filling-controlled Mott metal-insulator transition of a rare earth titanate
• The effect of hole-doping on the magnetic properties of Nd1-xTiO3