Mott electrons in an artificial graphenelike crystal of rare-earth nickelate

S Middey, D Meyers, D Doennig, M Kareev, X Liu… - Physical review …, 2016 - APS
S Middey, D Meyers, D Doennig, M Kareev, X Liu, Y Cao, Z Yang, J Shi, L Gu, PJ Ryan
Physical review letters, 2016APS
Deterministic control over the periodic geometrical arrangement of the constituent atoms is
the backbone of the material properties, which, along with the interactions, define the
electronic and magnetic ground state. Following this notion, a bilayer of a prototypical rare-
earth nickelate, NdNiO 3, combined with a dielectric spacer, LaAlO 3, has been layered
along the pseudocubic [111] direction. The resulting artificial graphenelike Mott crystal with
magnetic 3 d electrons has antiferromagnetic correlations. In addition, a combination of …
Deterministic control over the periodic geometrical arrangement of the constituent atoms is the backbone of the material properties, which, along with the interactions, define the electronic and magnetic ground state. Following this notion, a bilayer of a prototypical rare-earth nickelate, , combined with a dielectric spacer, , has been layered along the pseudocubic [111] direction. The resulting artificial graphenelike Mott crystal with magnetic electrons has antiferromagnetic correlations. In addition, a combination of resonant X-ray linear dichroism measurements and ab initio calculations reveal the presence of an ordered orbital pattern, which is unattainable in either bulk nickelates or nickelate based heterostructures grown along the [001] direction. These findings highlight another promising venue towards designing new quantum many-body states by virtue of geometrical engineering.
American Physical Society