Provoking topology by octahedral tilting in strained SrNbO$_3$

Alla Chikina; Victor Rosendal; Hang Li; Eduardo B. Guedes; Marco Caputo; Nicholas Clark Plumb; Ming Shi; Dirch Hjorth Petersen; Mads Brandbyge; Walber Hugo Brito; Ekaterina Pomjakushina; Valerio Scagnoli; Jike Lyu; Marisa Medarde; Elizabeth Skoropata; Urs Staub; Shih-Wen Huang; Felix Baumberger; Nini Pryds; Milan Radovic

arXiv · 2311.06072

Provoking topology by octahedral tilting in strained SrNbO$_3$

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Abstract

Transition metal oxides with a wide variety of electronic and magnetic properties offer an extraordinary possibility to be a platform for developing future electronics based on unconventional quantum phenomena, for instance, the topology. The formation of topologically non-trivial states is related to crystalline symmetry, spin-orbit coupling, and magnetic ordering. Here, we demonstrate how lattice distortions and octahedral rotation in SrNbO$_3$ films induce the band topology. By employing angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT) calculations, we verify the presence of in-phase $a^0a^0c^+$ octahedral rotation in ultra-thin SrNbO$_3$ films, which causes the formation of topologically-protected Dirac band crossings. Our study illustrates that octahedral engineering can be effectively exploited for implanting and controlling quantum topological phases in transition metal oxides.

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Alla Chikina, Victor Rosendal, Hang Li, Eduardo B. Guedes, Marco Caputo, Nicholas Clark Plumb, Ming Shi, Dirch Hjorth Petersen, Mads Brandbyge, Walber Hugo Brito, Ekaterina Pomjakushina, Valerio Scagnoli, Jike Lyu, Marisa Medarde, Elizabeth Skoropata, Urs Staub, Shih-Wen Huang, Felix Baumberger, Nini Pryds, Milan Radovic. 2023-11-10. Provoking topology by octahedral tilting in strained SrNbO$_3$. https://arxiv.org/abs/2311.06072

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