Common effect of chemical and external pressures on the magnetic properties of $R$CoPO ($R$ = La, Pr, Nd, Sm). II

Abstract

The direct correspondence between Co band ferromagnetism and structural parameters is investigated in the pnictide oxides $R$CoPO for different rare-earth ions ($R$ = La, Pr, Nd, Sm) by means of muon-spin spectroscopy and {\it ab-initio} calculations, complementing our results published previously [G. Prando {\it et al.}, {\it Phys. Rev. B} {\bf 87}, 064401 (2013)]. Both the transition temperature to the ferromagnetic phase $T_{{}_{\text{C}}}$ and the volume of the crystallographic unit cell $V$ are found to be conveniently tuned by the $R$ ionic radius and/or external pressure. A linear correlation between $T_{{}_{\text{C}}}$ and $V$ is reported and {\it ab-initio} calculations unambiguously demonstrate a full equivalence of chemical and external pressures. As such, $R$ ions are shown to be influencing the ferromagnetic phase only via the induced structural shrinkage without involving any active role from the electronic $f$ degrees of freedom, which are only giving a sizeable magnetic contribution at much lower temperatures.

8 pages, 5 figures

References in corpus (13)

• LaFeAsO${}_{1-x}$F${}_x$: A low carrier density superconductor near itinerant magnetism
• Near-degeneracy of several pairing channels in multiorbital models for the Fe-pnictides
• Doping-dependent Phase Diagram of LaO{\it M}As ({\it M}=V--Cu) and Electron-type Superconductivity near Ferromagnetic Instability
• Itinerant Ferromagnetism in layered crystals LaCoOX (X = P, As)
• CeRuPO: A rare example of a Ferromagnetic Kondo lattice
• A variable temperature study of the crystal and magnetic structures of the giant magnetoresistant materials LnMnAsO (Ln = La, Nd)
• Common effect of chemical and external pressures on the magnetic properties of RECoPO (RE = La, Pr)
• Structural trends from a consistent set of single-crystal data of REFeAsO (RE = La, Ce, Pr, Nd, Sm, Gd, and Tb)
• Colossal Magnetoresistance in the Mn2+ Oxypnictides NdMnAsO1-xFx
• Coupling between 4f and itinerant electrons in SmFeAsO1-xFx (0.15 < x < 0.2) superconductors: an NMR study
• Mutual independence of critical temperature and superfluid density under pressure in optimally electron-doped superconducting LaFeAsO${}_{1-x}$F${}_x$
• Phase separation at the magnetic-superconducting transition in La${}_{0.7}$Y${}_{0.3}$FeAsO${}_{1-x}$F${}_x$
• Effect of external pressure on the magnetic properties of $R$CoAsO ($R$ = La, Pr, Sm): a $\mu$SR study

Cited by in corpus (5)

• Influence of hydrostatic pressure on the bulk magnetic properties of Eu${}_2$Ir${}_2$O${}_7$
• Monopole-limited nucleation of magnetism in Eu${}_2$Ir${}_2$O${}_7$
• Role of magnetic dopants in the phase diagram of Sm1111 pnictides: The Mn case
• Suppression of the magnetic order in CeFeAsO: non-equivalence of hydrostatic and chemical pressure
• Tuning the magnetocrystalline anisotropy in $R$CoPO by means of $R$ substitution: a ferromagnetic resonance study