Isotope effect in superconducting n-doped SrTiO<sub>3</sub>

Article Article scientifique Article Isotope effect in superconducting n-doped SrTiO<sub>3</sub> eng 2016 author Stucky Adrien 634204 author Scheerer Gernot 815037 author Ren Zhi 807947 author Jaccard Didier 79523 author Poumirol Jean-Marie 814989 author Barreteau Céline 817569 author Giannini Enrico 0000-0003-3536-4771 503364 author Van Der Marel Dirk 0000-0001-5266-9847 135104 10.1038/srep37582 2045-2322 http://www.nature.com/articles/srep37582 We report the influence on the superconducting critical temperature Tc in doped SrTiO3 of the substitution of the natural 16O atoms by the heavier isotope 18O. We observe that for a wide range of doping this substitution causes a strong (~50%) enhancement of Tc. Also the magnetic critical field Hc2 is increased by a factor ~2. Such a strong impact on Tc and Hc2, with a sign opposite to conventional superconductors, is unprecedented. The observed effect could be the consequence of strong coupling of the doped electrons to lattice vibrations (phonons), a notion which finds support in numerous optical and photo-emission studies. The unusually large size of the observed isotope effect supports a recent model for superconductivity in these materials based on strong coupling to the ferroelectric soft modes of SrTiO3. Dewey 500.2 33 Département de physique de la matière quantique 131 false 785 Groupe Van der Marel Scientific Reports 6 37582 e3cf1dbf-f46f-4534-b009-5bc68275bdcc Article (Published version) Public srep37582.pdf 2507936 application/pdf openAccess Faculté des sciences / Section de physique / Département de physique de la matière quantique

Title	Published in	Access level	OA Policy	Year	Views	Downloads

Isotope effect in superconducting n-doped SrTiO₃	Scientific Reports			2016	286	278

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