Scientists / Open questions

Nicola A. Spaldin

Multiferroics; computational materials physics

15 questions

Atomic-scale ferroelectric switching mechanisms and insulating switching paths in multiferroic BiFeO $_3$
Realizing the interfacial 'negative dead layer': interface-enhanced ferroelectricity at AO-terminated perovskite/simple-metal interfaces and its connection to the short-circuit polarization
Microscopic characterization of the phonon-driven non-equilibrium state in underdoped YBa2Cu3O6.5: many-body electronic structure, transient plane-to-chain charge transfer, and the link between lattice displacements and enhanced superconducting coherence
Beyond the idealized first-principles model of ferroelectric domain walls in BiFeO3: intrinsic spin spiral, full strain relaxation, and defect-mediated screening of wall magnetism and conductivity
Methodological maturation of the pseudo-self-interaction-corrected (pseudo-SIC) pseudopotential scheme: stable occupation-number self-consistency, systematic benchmarking, and transferability validation
Strain-driven morphotropic phase boundaries in single-composition perovskites: genericity, device-level viability, and the thermodynamic-kinetic limits of the two-phase region
Origin, quantitative microscopic description, and control of electronic conduction at ferroelectric domain walls in BiFeO3
Excitons and optical spectra of silicon nanocrystals with nonideal surfaces: quantitative treatment of incomplete passivation, disorder, reconstruction, and oxidation
Realization and verification of the first-principles-predicted double-perovskite multiferroic Bi $_2$ FeCrO $_6$ : full Fe/Cr B-site order, magnetic ground state, transition temperatures, and carrier doping
Stabilization and half-metallic character of metastable zinc-blende MnAs
Beyond-Hartree-Fock theory of orbital and magnetic ordering at the relaxed LaTiO3/SrTiO3 superlattice interface: correlation dynamics, ordering temperatures, and nonlinear SrTiO3 dielectric screening
Generality and defect-mediated screening of anisotropic domain-wall conductance in improper ferroelectric hexagonal manganites
Charge-state and correlation dependence of defect-mediated magnetic ordering in transition-metal-doped ZnO: the open questions left by Gopal and Spaldin's ab initio study
Stabilizing robust ferromagnetism in polycrystalline $\mathrm{Zn}_{1-x}\mathrm{Co}_x\mathrm{O}$ by p-type (hole) doping: experimental realization, converged magnetic-interaction calculations, and the role of defects
Testing the generality of the LO–TO splitting as a first-principles indicator of cation off-centricity and incipient metallicity beyond the IV–VI rocksalt chalcogenides

Back to open problems

Atomic-scale ferroelectric switching mechanisms and insulating switching paths in multiferroic BiFeO3_33​

Realizing the interfacial 'negative dead layer': interface-enhanced ferroelectricity at AO-terminated perovskite/simple-metal interfaces and its connection to the short-circuit polarization

Microscopic characterization of the phonon-driven non-equilibrium state in underdoped YBa2Cu3O6.5: many-body electronic structure, transient plane-to-chain charge transfer, and the link between lattice displacements and enhanced superconducting coherence

Beyond the idealized first-principles model of ferroelectric domain walls in BiFeO3: intrinsic spin spiral, full strain relaxation, and defect-mediated screening of wall magnetism and conductivity

Methodological maturation of the pseudo-self-interaction-corrected (pseudo-SIC) pseudopotential scheme: stable occupation-number self-consistency, systematic benchmarking, and transferability validation

Strain-driven morphotropic phase boundaries in single-composition perovskites: genericity, device-level viability, and the thermodynamic-kinetic limits of the two-phase region

Origin, quantitative microscopic description, and control of electronic conduction at ferroelectric domain walls in BiFeO3

Excitons and optical spectra of silicon nanocrystals with nonideal surfaces: quantitative treatment of incomplete passivation, disorder, reconstruction, and oxidation

Realization and verification of the first-principles-predicted double-perovskite multiferroic Bi2_22​FeCrO6_66​: full Fe/Cr B-site order, magnetic ground state, transition temperatures, and carrier doping

Stabilization and half-metallic character of metastable zinc-blende MnAs

Beyond-Hartree-Fock theory of orbital and magnetic ordering at the relaxed LaTiO3/SrTiO3 superlattice interface: correlation dynamics, ordering temperatures, and nonlinear SrTiO3 dielectric screening

Generality and defect-mediated screening of anisotropic domain-wall conductance in improper ferroelectric hexagonal manganites

Charge-state and correlation dependence of defect-mediated magnetic ordering in transition-metal-doped ZnO: the open questions left by Gopal and Spaldin's ab initio study

Stabilizing robust ferromagnetism in polycrystalline Zn1−xCoxO\mathrm{Zn}_{1-x}\mathrm{Co}_x\mathrm{O}Zn1−x​Cox​O by p-type (hole) doping: experimental realization, converged magnetic-interaction calculations, and the role of defects

Testing the generality of the LO–TO splitting as a first-principles indicator of cation off-centricity and incipient metallicity beyond the IV–VI rocksalt chalcogenides

Atomic-scale ferroelectric switching mechanisms and insulating switching paths in multiferroic BiFeO $_3$

Realization and verification of the first-principles-predicted double-perovskite multiferroic Bi $_2$ FeCrO $_6$ : full Fe/Cr B-site order, magnetic ground state, transition temperatures, and carrier doping

Stabilizing robust ferromagnetism in polycrystalline $\mathrm{Zn}_{1-x}\mathrm{Co}_x\mathrm{O}$ by p-type (hole) doping: experimental realization, converged magnetic-interaction calculations, and the role of defects