Composite antiferromagnetic and orbital order with altermagnetic properties at a cuprate/manganite interface

Abstract

Heterostructures from complex oxides allow one to combine various electronic and magnetic orders as to induce new quantum states. A prominent example is the coupling between superconducting and magnetic orders in multilayers from high-Tc cuprates and manganites. A key role is played here by the interfacial CuO2 layer whose distinct properties remain to be fully understood. Here, we study with resonant inelastic X-ray scattering (RIXS) the magnon excitations of this interfacial CuO2 layer. In particular, we show that the underlying antiferromagnetic exchange interaction at the interface is strongly suppressed to J ~ 70 meV, as compared to J ~ 130 meV for the CuO2 layers away from the interface. Moreover, we observe an anomalous momentum dependence of the intensity of the interfacial magnon mode and show that it suggests that the antiferromagnetic order is accompanied by a particular kind of orbital order that yields a so-called altermagnetic state. Such a two-dimensional altermagnet has recently been predicted to enable new spintronic applications and superconducting proximity effects.

References in corpus (15)

• 2D materials and van der Waals heterostructures
• Direct observation of competition between superconductivity and charge density wave order in YBa2Cu3Oy
• Altermagnetism: spin-momentum locked phase protected by non-relativistic symmetries
• Giant and tunneling magnetoresistance effects from anisotropic and valley-dependent spin-momentum interactions in antiferromagnets
• Spin-Orbital Separation in the quasi 1D Mott-insulator Sr2CuO3
• Strength of the Spin-Fluctuation-Mediated Pairing Interaction in a High-Temperature Superconductor
• Two energy scales in the spin excitations of the high-T_c superconductor La${}_{2-x}$Sr${}_x$CuO${}_4$
• Experimental Determination of Momentum-Resolved Electron-Phonon Coupling
• Polarization resolved Cu $L_3$-edge resonant inelastic x-ray scattering of orbital and spin excitations in NdBa${}_2$Cu${}_3$O${}_{7-\delta }$
• Emerging research landscape of altermagnetism
• Multiple-magnon excitations shape the spin spectrum of cuprate parent compounds
• Pseudogap and Fermi-arcs in underdoped cuprates
• Controlling the strength of ferromagnetic order in YBa${}_2$Cu${}_3$O${}_7$/La${}_{2/3}$Ca${}_{1/3}$MnO${}_3$ multilayers
• X-ray absorption spectroscopy study of the electronic and magnetic proximity effects in YBa${}_2$Cu${}_3$O${}_7$/La${}_{2/3}$Ca${}_{1/3}$MnO${}_3$ and La${}_{2-x}$Sr${}_x$CuO${}_4$/La${}_{2/3}$Ca${}_{1/3}$MnO${}_3$ multilayers
• Quenched Magnon excitations by oxygen sublattice reconstruction in (SrCuO${}_2$)${}_n$/(SrTiO${}_3$)${}_2$ superlattices

Cited by in corpus (1)

• Giant spatial anisotropy of magnon lifetime in altermagnets