title: Strategies for increasing the Néel temperature of magnetoelectric Fe2TeO6.
abstract: Ways to increase the Néel temperature TN in the magnetoelectric Fe2TeO6 antiferromagnet are explored with the help of first-principles calculations. Substitution of larger ions like Zr or Hf for tellurium increases the superexchange angles. The compensating O vacancies tend to form bound complexes with Zr dopants, which do not degrade the electronic band gap. TN is estimated to increase by 15% at 12.5% Te → Zr substitution with such compensation. Substitution of N for O is favorable due to the decreased charge-transfer gap. The overall effect for N(3-) substitution compensated by O vacancies is estimated at 3-4% TN enhancement per 1% O → N substitution. A 1% compressive (0 0 1) epitaxial strain enhances TN by about 6%.
authors.affiliation: Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Sai
authors.initials: S
authors.lastname: Mu
authors.forename: Kirill D
authors.initials: KD
authors.lastname: Belashchenko