Excess iron deintercalation induced superconductivity in Fe(Te, Se) and Fe(Te, S) via sulfur annealing

K. Deguchi, A. Yamashita, T. Yamaki, H. Hara, S. Demura, S. J. Denholme, M. Fujioka, H. Okazaki, H. Takeya, T. Yamaguchi, Y. Takano