01782nas a2200277 4500008004100000022001300041245012600054210006900180260003000249490000700279520093000286100001601216700001701232700001401249700001701263700001801280700001301298700001101311700001701322700001301339700001901352700002101371700001401392700002401406856007401430 2016 eng d a2469995000aStrain-induced nonsymmorphic symmetry breaking and removal of Dirac semimetallic nodal line in an orthoperovskite iridate0 aStraininduced nonsymmorphic symmetry breaking and removal of Dir bAmerican Physical Society0 v933 aBy using a combination of heteroepitaxial growth, structure refinement based on synchrotron x-ray diffraction, and first-principles calculations, we show that the symmetry-protected Dirac line nodes in the topological semimetallic perovskite SrIrO3 can be lifted simply by applying epitaxial constraints. In particular, the Dirac gap opens without breaking the Pbnm mirror symmetry. In virtue of a symmetry-breaking analysis, we demonstrate that the original symmetry protection is related to the n-glide operation, which can be selectively broken by different heteroepitaxial structures. This symmetry protection renders the nodal line a nonsymmorphic Dirac semimetallic state. The results highlight the vital role of crystal symmetry in spin-orbit-coupled correlated oxides and provide a foundation for experimental realization of topological insulators in iridate-based heterostructures. © 2016 American Physical Society.1 aLiu, J., F.1 aKriegner, D.1 aHorak, L.1 aPuggioni, D.1 aSerrao, Rayan1 aChen, R.1 aYi, D.1 aFrontera, C.1 aHoly, V.1 aVishwanath, A.1 aRondinelli, J.M.1 aMarti, X.1 aRamesh, Ramamoorthy uhttps://rameshlab.lbl.gov/publications/strain-induced-nonsymmorphic-0