skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Strong correlations between vacancy and magnetic ordering in superconducting K 0.8 Fe 2 y Se 2

Authors:
; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1260308
Grant/Contract Number:
FG02-01ER45927
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 94; Journal Issue: 2; Related Information: CHORUS Timestamp: 2016-07-05 18:11:43; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Yang, J., Duan, C., Huang, Q., Brown, C., Neuefeind, J., and Louca, Despina. Strong correlations between vacancy and magnetic ordering in superconducting K 0.8 Fe 2 − y Se 2. United States: N. p., 2016. Web. doi:10.1103/PhysRevB.94.024503.
Yang, J., Duan, C., Huang, Q., Brown, C., Neuefeind, J., & Louca, Despina. Strong correlations between vacancy and magnetic ordering in superconducting K 0.8 Fe 2 − y Se 2. United States. doi:10.1103/PhysRevB.94.024503.
Yang, J., Duan, C., Huang, Q., Brown, C., Neuefeind, J., and Louca, Despina. 2016. "Strong correlations between vacancy and magnetic ordering in superconducting K 0.8 Fe 2 − y Se 2". United States. doi:10.1103/PhysRevB.94.024503.
@article{osti_1260308,
title = {Strong correlations between vacancy and magnetic ordering in superconducting K 0.8 Fe 2 − y Se 2},
author = {Yang, J. and Duan, C. and Huang, Q. and Brown, C. and Neuefeind, J. and Louca, Despina},
abstractNote = {},
doi = {10.1103/PhysRevB.94.024503},
journal = {Physical Review B},
number = 2,
volume = 94,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevB.94.024503

Save / Share:
  • Cited by 2
  • Using high-pressure magnetotransport techniques we have discovered superconductivity in Bi2Te, a member of the infinitely adaptive (Bi2)n(Bi2Te3)m series, whose end members, Bi and Bi2Te3, can be tuned to display topological surface states or superconductivity. Bi2Te has a maximum Tc= 8.6 K at P= 14.5 GPa and goes through multiple high pressure phase transitions, ultimately collapsing into a bcc structure that suggests a universal behavior across the series. High-pressure magnetoresistance and Hall measurements suggest a semi-metal to metal transition near 5.4 GPa, which accompanies the hexagonal to intermediate phase transition seen via x-ray diffraction measurements. In addition, the linearity of Hc2(T)more » exceeds the WHH limit, even in the extreme spin-orbit scattering limit, yet is consistent with other strong spin-orbit materials. Considering these results in combination with similar reports on strong spin-orbit scattering materials seen in the literature, we suggest the need for a new theory that can address the unconventional nature of their superconducting states.« less
  • Cited by 1
  • By simultaneously displaying magnetism and superconductivity in a single phase, the iron-based superconductors provide a model system for the study of magnetism's role in superconductivity. The class of intercalated iron selenide superconductors is unique among these in having the additional property of phase separation and coexistence of two distinct phases—one majority phase with iron vacancy ordering and strong antiferromagnetism, and the other a poorly understood minority microscopic phase with a contested structure. Adding to the intrigue, the majority phase has never been found to show superconductivity on its own while the minority phase has never been successfully synthesized separate frommore » the majority phase. In order to better understand this minority phase, a series of high-quality Cs xFe 2–ySe 2 single crystals with (0.8 ≤ x ≤ 1;0 ≤ y ≤ 0.3) were grown and studied. Neutron and x-ray powder diffraction performed on ground crystals show that the average I4/mmm structure of the minority phase is distinctly different from the high-temperature I4/mmm parent structure. Moreover, single-crystal diffraction reveals the presence of discrete superlattice reflections that remove the degeneracy of the Cs sites in both the majority and minority phases and reduce their structural symmetries from body centered to primitive. Group theoretical analysis in conjunction with structural modeling shows that the observed superlattice reflections originate from three-dimensional Cs vacancy ordering. This model predicts a 25% vacancy of the Cs site in the minority phase which is consistent with the site's refined occupancy. Magnetization measurements performed in tandem with neutron single-crystal diffraction provide evidence that the minority phase is the host of superconductivity. Lastly, our results also reveal a superconducting dome in which the superconducting transition temperature varies as a function of the nominal valence of iron.« less