Author Correction: Improving superconductivity in BaFeAs-based crystals by cobalt clustering and electronic uniformity.

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Improving superconductivity in BaFeAs-based crystals by cobalt clustering and electronic uniformity.

Quantum materials such as antiferromagnets or superconductors are complex in that chemical, electronic, and spin phenomena at atomic scales can manifest in their collective properties. Although there are some clues for designing such materials, they remain mainly unpredictable. In this work, we find that enhancement of transition temperatures in BaFeAs-based crystals are caused by removing local-lattice strain and electronic-structure disorder by thermal annealing.