Magnetism in iridate heterostructures leveraged by structural distortions

Abstract

Fundamental control of magnetic coupling through heterostructure morphology is a prerequisite for rational engineering of magnetic ground states. We report the tuning of magnetic interactions in superlattices composed of single and bilayers of SrIrO3 inter-spaced with SrTiO3 in analogy to the Ruddlesden-Popper series iridates. Magnetic scattering shows predominately c-axis antiferromagnetic orientation of the magnetic moments for the bilayer, as in Sr3Ir2O7. However, the magnetic excitation gap, measured by resonant inelastic x-ray scattering, is quite different between the two structures, evidencing a significant change in the stability of the competing magnetic phases. In contrast, the single layer iridate hosts a more bulk-like gap. We find these changes are driven by bending of the c-axis Ir-O-Ir bond, which is much weaker in the single layer, and subsequent local environment changes, evidenced through x-ray diffraction and magnetic excitation modeling. Our findings demonstrate how large changes in the magnetic interactions can be tailored and probed in spin-orbit coupled heterostructures by engineering subtle structural modulations.

Document Details

Document Type
Pub Defense Publication
Publication Date
Mar 12, 2019
Source ID
10.1038/s41598-019-39422-9

Entities

People

  • Christina Frederick
  • D Meyers
  • D. Casa
  • D. Haskel
  • E. Karapetrova
  • G. Fabbris
  • Jeremy Yang
  • Jian Liu
  • Jiaqi Lin
  • Jong-woo Kim
  • Lin Hao
  • Lukas Horak
  • Mark P. M. Dean
  • Mary Upton
  • N. Traynor
  • Neil J. Robinson
  • Philip J. Ryan
  • T. Gög
  • X. Liu
  • Yongseong Choi
  • Yue Cao

Organizations

  • Chinese Academy of Sciences
  • Ministry of Science and Technology of the People's Republic of China
  • United States Department of Defense
  • United States Department of Energy

Tags

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.
  • Superconducting Magnet Technology

Technology Areas

  • Space