Improved control of atomic layering in perovskite-related homologous series
Matthew R. Barone,
Natalie M. Dawley,
Hari P. Nair,
Berit H. Goodge,
Megan E. Holtz,
Arsen Soukiassian,
Erin E. Fleck,
Kiyoung Lee,
Yunfa Jia,
Tassilo Heeg,
Refael Gatt,
Yuefeng Nie,
David A. Muller,
Lena F. Kourkoutis,
Darrell G. Schlom
Affiliations
Matthew R. Barone
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
Natalie M. Dawley
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
Hari P. Nair
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
Berit H. Goodge
School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
Megan E. Holtz
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
Arsen Soukiassian
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
Erin E. Fleck
School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
Kiyoung Lee
Samsung Advanced Institute of Technology (SAIT), Samsung Electronics, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16678, South Korea
Yunfa Jia
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
Tassilo Heeg
Heeg Vacuum Engineering, Kerpen, Germany
Refael Gatt
Quantum Designed Materials Ltd., Rehovot, Israel
Yuefeng Nie
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China
David A. Muller
School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
Lena F. Kourkoutis
School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, USA
Darrell G. Schlom
Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA
Homologous series are layered phases that can have a range of stoichiometries depending on an index n. Examples of perovskite-related homologous series include (ABO3)nAO Ruddlesden–Popper phases and (Bi2O2) (An−1BnO3n+1) Aurivillius phases. It is challenging to precisely control n because other members of the homologous series have similar stoichiometry and a phase with the desired n is degenerate in energy with syntactic intergrowths among similar n values; this challenge is amplified as n increases. To improve the ability to synthesize a targeted phase with precise control of the atomic layering, we apply the x-ray diffraction (XRD) approach developed for superlattices of III–V semiconductors to measure minute deviations from the ideal structure so that they can be quantitatively eradicated in subsequent films. We demonstrate the precision of this approach by improving the growth of known Ruddlesden–Popper phases and ultimately, by synthesizing an unprecedented n = 20 Ruddlesden–Popper phase, (ATiO3)20AO where the A-site occupancy is Ba0.6Sr0.4. We demonstrate the generality of this method by applying it to Aurivillius phases and the Bi2Sr2Can–1CunO2n+4 series of high-temperature superconducting phases.
