Charge ordering and magneto-polarons in Na${}_{0.82}$CoO${}_2$

Abstract

Using spectral ellipsometry, we have measured the dielectric function of a Na${}_{0.82(2)}$CoO${}_2$ crystal that exhibits bulk antiferromagnetism with T${}_N$=19.8 K. We identify two prominent transitions as a function of temperature. The first one at 280 K involves marked changes of the electronic and the lattice response that are indicative of charge ordering in the CoO${}_2$ layers. The second transition coincides with T${}_N$=19.8 K and reveals a sizeable spin-charge coupling. The data are discussed in terms of charge ordering and formation of magneto-polarons due to a charge-induced spin-state transition of adjacent Co${}^{3+}$ ions.

References in corpus (14)

• Spin entropy as the likely source of enhanced thermopower in $\rm\bf Na_xCo_2O_4
• Fermi surface and quasiparticle dynamics of Na(x)CoO2 {x=0.7} investigated by Angle-Resolved Photoemission Spectroscopy
• Unconventional Superconductivity and Electron Correlations in Cobalt Oxyhydrate Na${}_{0.35}$CoO${}_2$$\cdot y$H${}_2$O
• ARPES on Na${}_{0.6}$CoO${}_2$: Fermi surface, extended flat dispersion, and unusual band splitting
• Quantum Critical Behavior and Possible Triplet Superconductivity in Electron Doped CoO2 Sheets
• Crystal Structure of the Sodium Cobaltate Deuterate Superconductor NaxCoO2o4xD2O (x=1/3)
• Bulk antiferromagnetism in $\mathbf{N}{\mathbf{a}}_{0.82}\mathbf{Co}{\mathbf{O}}_2$ single crystals
• Hidden magnetic transitions in thermoelectric layered cobaltite, [Ca${}_2$CoO${}_3$]${}_{0.62}$[CoO${}_2$]
• Structure and Dynamics of Superconducting NaxCoO(2) Hydrate and Its Unhydrated Analog
• Dome-shaped magnetic phase diagram of thermoelectric layered cobaltites
• Possible spin triplet superconductivity in Na${}_x$CoO${}_2\cdot y$H${}_2$0
• Unconventional Charge Ordering in Na0.70CoO2 below 300 K
• The infrared spectrum of Na_0.57CoO_2
• Spin states and phase separation in La_{1-x}Sr_{x}CoO_3 (x=0.15, 0.25, 0.35) films: optical, magneto-optical and magneto-transport studies

Cited by in corpus (37)

• Large enhancement of the thermopower in Na${}_x$CoO${}_2$ at high Na doping
• Magnetic ordering and spin waves in $\mathbf{N}{\mathbf{a}}_{0.82}\mathbf{Co}{\mathbf{O}}_2$
• Three-Dimensional Spin Fluctuations in Na0.75CoO2
• Bad Metals from Fluctuating Density Waves
• Evidence of a single nonmagnetic Co3+ state in the Na1CoO2 cobaltate
• Spin-reorientation-induced band gap in Fe${}_3$Sn${}_2$: Optical signatures of Weyl nodes
• Infrared probe of the electronic structure and charge dynamics in Na${}_{0.7}$CoO${}_2$
• Non-magnetic insulator state in Na1CoO2 and phase separation of Na vacancies
• Optical study of RbV${}_3$Sb${}_5$: Multiple density-wave gaps and phonon anomalies
• Na content dependence of superconductivity and the spin correlations in Na_{x}CoO_{2}\cdot 1.3H_{2}O
• Na ordering imprints a metallic kagome lattice onto the Co planes of Na2/3CoO2
• The infrared conductivity of Na${}_x$CoO${}_2$: evidence of gapped states
• Anomalous electronic Raman scattering in Na_xCoO_2 H_2O
• Electrodynamics of correlated electron matter
• Anisotropic quasiparticle renormalization in Na0.73CoO2: role of inter-orbital interactions and magnetic correlations
• Magnetic properties of spin-orbital polarons in lightly doped cobaltates
• X-ray absorption spectroscopy on layered cobaltates Na_xCoO_2
• Spin gaps and magnetic structure of NaxCoO2
• Optical Properties and Correlation Effects in NaxCoO2
• Electron-boson mode coupling and the pseudogap of Na${}_x$CoO${}_2$ by infrared spectroscopy
• The origin of strong correlations and superconductivity in Na${}_x$CoO${}_2$
• Stripe correlations in Na${}_{0.75}$CoO${}_2$
• Infrared Conductivity and Charge Ordering in NaCoO2
• Crystal-to-stripe reordering of sodium ions in NaxCoO2 (x>=0.75)
• Coupled spin-charge order in frustrated itinerant triangular magnets
• Itinerant and localized magnetism on the triangular lattice: sodium rich phases of Na${}_x$CoO${}_2$
• Noncollinear and noncoplanar magnetic order in the extended Hubbard model on anisotropic triangular lattice
• Localized versus itinerant magnetic moments in Na0.72CoO2
• Quantum-Acoustical Drude Peak Shift
• Signatures of polaronic charge ordering in optical and dc conductivity using dynamical mean field theory
• Origin of the electron disproportionation in the metallic sodium cobaltates
• Revisiting the crystal electric field of P2-NaxCoO2 for the intermediate spin state of Co3+
• Reflectivity measurements in uniaxial superconductors: a methodological discussion applied to the case of La(2-x)Sr(x)CuO(4)
• Hard x-ray spectroscopy in NaxCoO2 and superconducting NaxCoO2 - yH2O: A view on the bulk Co electronic properties
• Enhanced low energy fluctuations and increasing out-of-plane coherence in vacancy ordered NaxCoO2
• Infrared Hall conductivity of Na${}_{0.7}$CoO${}_2$
• Sodium ion ordering of Na0.77CoO2 under competing multi-vacancy cluster, superlattice and domain formation