Spectroscopic evidence of spin- state excitation in d- electron correlated semiconductor FeSb2

• 成果类型: Article
• 署名作者: Li, Huayao; Wang, Guohua; Ding, Ning; Ren, Quan; Zhao, Gan; Lin, Wenting; Yang, Jinchuan; Yan, Wensheng; Li, Qian; Yang, Run; Yuan, Shijun; Denlinger, Jonathan D.; Wang, Zhenxing; Zhang, Xiaoqian; Wray, L. Andrew; Dong, Shuai; Qian, Dong; Miao, Lin
• 署名单位: Southeast University - China; Shanghai Jiao Tong University; Chinese Academy of Sciences; University of Science & Technology of China, CAS; United States Department of Energy (DOE); Lawrence Berkeley National Laboratory; Huazhong University of Science & Technology; Huazhong University of Science & Technology; New York University; Collaborative Innovation Center of Advanced Microstructures (CICAM); Nanjing University; Shanghai Jiao Tong University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-13248
• DOI: 10.1073/pnas.2321193121
• 发表日期: 2024-07-09
• 关键词: total-energy calculations; x-ray-absorption; TRANSITION; marcasite; pyrite

摘要

Iron antimonide (FeSb 2 ) has been investigated for decades due to its puzzling electronic properties. It undergoes the temperature- controlled transition from an insulator to an ill- defined metal, with a cross- over from diamagnetism to paramagnetism. Extensive efforts have been made to uncover the underlying mechanism, but a consensus has yet to be reached. While macroscopic transport and magnetic measurements can be explained by different theoretical proposals, the essential spectroscopic evidence required to distinguish the physical origin is missing. In this paper, through the use of X- ray absorption spectroscopy and atomic multiplet simulations, we have observed the mixed spin states of 3 d 6 configuration in FeSb 2 . Furthermore, we reveal that the enhancement of the conductivity, whether induced by temperature or doping, is characterized by populating the high- spin state from the low- spin state. Our work constitutes vital spectroscopic evidence that the electrical/magnetical transition in FeSb 2 is directly associated with the spin- state excitation.