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Abstract It has been suggested that Ba3In2O6might be a high-Tcsuperconductor. Experimental investigation of the properties of Ba3In2O6was long inhibited by its instability in air. Recently epitaxial Ba3In2O6with a protective capping layer was demonstrated, which finally allows its electronic characterization. The optical bandgap of Ba3In2O6is determined to be 2.99 eV in-the (001) plane and 2.83 eV along thec-axis direction by spectroscopic ellipsometry. First-principles calculations were carried out, yielding a result in good agreement with the experimental value. Various dopants were explored to induce (super-)conductivity in this otherwise insulating material. NeitherA- norB-site doping proved successful. The underlying reason is predominately the formation of oxygen interstitials as revealed by scanning transmission electron microscopy and first-principles calculations. Additional efforts to induce superconductivity were investigated, including surface alkali doping, optical pumping, and hydrogen reduction. To probe liquid-ion gating, Ba3In2O6was successfully grown epitaxially on an epitaxial SrRuO3bottom electrode. So far none of these efforts induced superconductivity in Ba3In2O6,leaving the answer to the initial question of whether Ba3In2O6is a high-Tcsuperconductor to be ‘no’ thus far.
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Polymorphism in A 3 MF 6 (A = Rb, Cs; M = Al, Ga) grown using mixed halide fluxes
Single crystals of A3MF6(A = Rb, Cs; M = Al, Ga) were grown from mixed alkali chloride/fluoride fluxes. The polymorphism of each compound was studiedviaTGA/DSC and high temperature X-ray diffraction.
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- PAR ID:
- 10491732
- Publisher / Repository:
- The Royal Society of Chemistry
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 52
- Issue:
- 24
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 8425 to 8433
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1039/D3DT00352C
