title: Colossal resistance switching and band gap modulation in a perovskite nickelate by electron doping.
abstract: The electronic properties of correlated oxides are exceptionally sensitive to the orbital occupancy of electrons. Here we report an electron doping strategy via a chemical route, where interstitial dopants (for example, hydrogen) can be reversibly intercalated, realizing a sharp phase transition in a model correlated perovskite nickelate SmNiO3. The electron configuration of eg orbital of Ni(3+) t2g(6)eg(1) in SmNiO3 is modified by injecting and anchoring an extra electron, forming a strongly correlated Ni(2+) t2g(6)eg(2) structure leading to the emergence of a new insulating phase. A reversible resistivity modulation greater than eight orders of magnitude is demonstrated at room temperature. A solid-state room temperature non-volatile proton-gated phase-change transistor is demonstrated based on this principle, which may inform new materials design for correlated oxide devices. Electron doping-driven phase transition accompanied by large conductance changes and band gap modulation opens up new directions to explore emerging electronic and photonic devices with correlated oxide systems.
authors.affiliation: 1] School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA [2].
authors.forename: Jian
authors.initials: J
authors.lastname: Shi
authors.affiliation: 1] School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA [2].
authors.forename: You
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
authors.forename: Shriram
authors.initials: S
authors.lastname: Ramanathan