Strain Control of Fermiology and Many-Body Interactions in Two-Dimensional Ruthenates

B. Burganov; C. Adamo; A. Mulder; M. Uchida; P. D. C. King; J. W. Harter; D. E. Shai; A. S. Gibbs; A. P. Mackenzie; R. Uecker; M. Bruetzam; M. R. Beasley; C. J. Fennie; D. G. Schlom; K. M. Shen

doi:10.1103/physrevlett.116.197003

arXiv · 1605.05669

Strain Control of Fermiology and Many-Body Interactions in Two-Dimensional Ruthenates

B. Burganov·C. Adamo·A. Mulder·M. Uchida·P. D. C. King·J. W. Harter·D. E. Shai·A. S. Gibbs·A. P. Mackenzie·R. Uecker·M. Bruetzam·M. R. Beasley·C. J. Fennie·D. G. Schlom·K. M. Shen

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Abstract

Here we demonstrate how the Fermi surface topology and quantum many-body interactions can be manipulated via epitaxial strain in the spin-triplet superconductor Sr$_2$RuO$_4$ and its isoelectronic counterpart Ba$_2$RuO$_4$ using oxide molecular beam epitaxy (MBE), \emph{in situ} angle-resolved photoemission spectroscopy (ARPES), and transport measurements. Near the topological transition of the $\gamma$ Fermi surface sheet, we observe clear signatures of critical fluctuations, while the quasiparticle mass enhancement is found to increase rapidly and monotonically with increasing Ru-O bond distance. Our work demonstrates the possibilities for using epitaxial strain as a disorder-free means of manipulating emergent properties, many-body interactions, and potentially the superconductivity in correlated materials.

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B. Burganov, C. Adamo, A. Mulder, M. Uchida, P. D. C. King, J. W. Harter, D. E. Shai, A. S. Gibbs, A. P. Mackenzie, R. Uecker, M. Bruetzam, M. R. Beasley, C. J. Fennie, D. G. Schlom, K. M. Shen. 2016-05-18. Strain Control of Fermiology and Many-Body Interactions in Two-Dimensional Ruthenates. https://doi.org/10.1103/physrevlett.116.197003

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