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arXiv · 1701.08942

Dimensionality-strain phase diagram of strontium iridates

Bongjae Kim·Peitao Liu·Cesare Franchini
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Abstract

The competition between spin-orbit coupling, bandwidth ($W$) and electron-electron interaction ($U$) makes iridates highly susceptible to small external perturbations, which can trigger the onset of novel types of electronic and magnetic states. Here we employ {\em first principles} calculations based on density functional theory and on the constrained random phase approximation to study how dimensionality and strain affect the strength of $U$ and $W$ in (SrIrO$_3$)$_m$/(SrTiO$_3$) superlattices. The result is a phase diagram explaining two different types of controllable magnetic and electronic transitions, spin-flop and insulator-to-metal, connected with the disruption of the $J_{eff}=1/2$ state which cannnot be understood within a simplified local picture.

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Bongjae Kim, Peitao Liu, Cesare Franchini. 2017-02-22. Dimensionality-strain phase diagram of strontium iridates. https://doi.org/10.1103/physrevb.95.115111

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