TY - JOUR
T1 - A Mott insulator continuously connected to iron pnictide superconductors
AU - Song, Yu
AU - Yamani, Zahra
AU - Cao, Chongde
AU - Li, Yu
AU - Zhang, Chenglin
AU - Chen, Justin S.
AU - Huang, Qingzhen
AU - Wu, Hui
AU - Tao, Jing
AU - Zhu, Yimei
AU - Tian, Wei
AU - Chi, Songxue
AU - Cao, Huibo
AU - Huang, Yao Bo
AU - Dantz, Marcus
AU - Schmitt, Thorsten
AU - Yu, Rong
AU - Nevidomskyy, Andriy H.
AU - Morosan, Emilia
AU - Si, Qimiao
AU - Dai, Pengcheng
PY - 2016/12/19
Y1 - 2016/12/19
N2 - Iron-based superconductivity develops near an antiferromagnetic order and out of a bad-metal normal state, which has been interpreted as originating from a proximate Mott transition. Whether an actual Mott insulator can be realized in the phase diagram of the iron pnictides remains an open question. Here we use transport, transmission electron microscopy, X-ray absorption spectroscopy, resonant inelastic X-ray scattering and neutron scattering to demonstrate that NaFe 1â 'x Cu x As near xâ ‰0.5 exhibits real space Fe and Cu ordering, and are antiferromagnetic insulators with the insulating behaviour persisting above the Néel temperature, indicative of a Mott insulator. On decreasing x from 0.5, the antiferromagnetic-ordered moment continuously decreases, yielding to superconductivity â 1/4x=0.05. Our discovery of a Mott-insulating state in NaFe 1â 'x Cu x As thus makes it the only known Fe-based material, in which superconductivity can be smoothly connected to the Mott-insulating state, highlighting the important role of electron correlations in the high-T c superconductivity.
AB - Iron-based superconductivity develops near an antiferromagnetic order and out of a bad-metal normal state, which has been interpreted as originating from a proximate Mott transition. Whether an actual Mott insulator can be realized in the phase diagram of the iron pnictides remains an open question. Here we use transport, transmission electron microscopy, X-ray absorption spectroscopy, resonant inelastic X-ray scattering and neutron scattering to demonstrate that NaFe 1â 'x Cu x As near xâ ‰0.5 exhibits real space Fe and Cu ordering, and are antiferromagnetic insulators with the insulating behaviour persisting above the Néel temperature, indicative of a Mott insulator. On decreasing x from 0.5, the antiferromagnetic-ordered moment continuously decreases, yielding to superconductivity â 1/4x=0.05. Our discovery of a Mott-insulating state in NaFe 1â 'x Cu x As thus makes it the only known Fe-based material, in which superconductivity can be smoothly connected to the Mott-insulating state, highlighting the important role of electron correlations in the high-T c superconductivity.
UR - http://www.scopus.com/inward/record.url?scp=85006713656&partnerID=8YFLogxK
U2 - 10.1038/ncomms13879
DO - 10.1038/ncomms13879
M3 - Article
AN - SCOPUS:85006713656
SN - 2041-1723
VL - 7
JO - Nature Communications
JF - Nature Communications
M1 - 13879
ER -