Strain-induced néel temperature enhancement in corundum-type Cr ₂O₃ and Fe₂O₃

The effect of strain on Néel temperature in corundum-type Cr ₂O₃ and Fe₂O₃ was theoretically studied. We calculated the exchange coupling constants up to the fifth-nearest neighbors using the first-principles density functional method and evaluated the Néel temperature using Monte Carlo simulation of the classical Heisenberg model. We showed that the Néel temperature is enhanced (decreased) by tensile (compressive) strain along the c-axis. The Néel temperatures of Cr₂O₃ and Fe₂O₃ are enhanced more than 20 and 7% by 5% strain of the crystal lattice, respectively.