Orbital-spin order and the origin of structural distortion in MgTi${}_2$O${}_4$

Abstract

We analyze electronic, magnetic, and structural properties of the spinel compound MgTi${}_2$O${}_4$ using the local density approximation+U method. We show how MgTi${}_2$O${}_4$ undergoes to a canted orbital-spin ordered state, where charge, spin and orbital degrees of freedom are frozen in a geometrically frustrated network by electron interactions. In our picture orbital order stabilize the magnetic ground state and controls the degree of structural distortions. The latter is dynamically derived from the cubic structure in the correlated LDA+U potential. Our ground-state theory provides a consistent picture for the dimerized phase of MgTi${}_2$O${}_4$, and might be applicable to frustrated materials in general.

arXiv comment6 pages, 6 figures

References in corpus (9)

• Spin Ice State in Frustrated Magnetic Pyrochlore Materials
• Orbitally-driven Peierls state in spinels
• Spin singlet formation in MgTi${}_2$O${}_4$: evidence of a helical dimerization pattern
• Deconfined quantum criticality and Neel order via dimer disorder
• The Role of hybridization in NaxCoO2 and the Effect of Hydration
• Valence bond crystal in a pyrochlore antiferromagnet with orbital degeneracy
• Valence-Bond Crystal, and Lattice Distortions in a Pyrochlore Antiferromagnet with Orbital Degeneracy
• Optical study of MgTi${}_2$O${}_4$: Evidence for an orbital-Peierls state
• The ground state phases of orbitally degenerate spinel oxides

Cited by in corpus (10)

• Emergent superconductivity in single crystalline ${\mathrm{MgTi}}_2{\mathrm{O}}_4$ films via structural engineering
• Ionic liquid gating induced two superconductor-insulator phase transitions in spinel oxide Li${}_{1\pm x}$Ti${}_2$O${}_{4-\delta }$
• Tetramer Orbital-Ordering induced Lattice-Chirality in Ferrimagnetic, Polar MnTi2O4
• Prediction for the singlet-triplet excitation energy for the spinel MgTi${}_2$O${}_4$ using first-principles diffusion Monte Carlo
• Possible routes to superconductivity in the surface layers of V-doped Mg${}_{1-\delta }$Ti${}_2$O${}_4$ through multiple charge transfers and suppression of Jahn-Teller activity
• Soft-Chemical Synthesis, Structure Evolution, and Insulator-to-Metal Transition in a Prototypical Metal Oxide, λ-RhO${}_2$
• Epitaxial stabilization of an orthorhombic Mg-Ti-O superconductor
• Surface-phase superconductivity in Mg-deficient V-doped MgTi${}_2$O${}_4$ spinel
• Evolution of orbital excitations from insulating to superconducting MgTi${}_2$O${}_4$ films
• Exploring the Electronic Nature of Spinel Oxides: A Review of Their Electron Interactions and Prospects