TY - JOUR
T1 - Synthesis and post-annealing effects of alkaline-metal-ethylenediamine- intercalated superconductors Ax(C2H8N 2)yFe2-zSe2 (A = Li, Na) with Tc = 45 K
AU - Noji, Takashi
AU - Hatakeda, Takehiro
AU - Hosono, Shohei
AU - Kawamata, Takayuki
AU - Kato, Masatsune
AU - Koike, Yoji
PY - 2014/9/15
Y1 - 2014/9/15
N2 - New iron-based intercalation superconductors Ax(C 2H8N2)yFe2- zSe2 (A = Li, Na) with Tc = 45 K have successfully been synthesized via intercalation of dissolved alkaline metal in ethylenediamine. The c-axis lengths of Ax(C2H 8N2)yFe2-zSe2 (A = Li, Na) are 20.74(7) Å and 21.9(1) Å, respectively, and are about 50% larger than that of KxFe2Se2, indicating that not only alkaline metal but also ethylenediamine is intercalated between the Se-Se layers of FeSe. It seems that the high-Tc of Ax(C2H8N2)yFe 2-zSe2 (A = Li, Na) is caused by the possible two-dimensional electronic structure due to the large c-axis length. Through the post-annealing in an evacuated glass tube, it has been found that Tc decreases with increasing post-annealing temperature and that deintercalation of EDA from the as-intercalated sample takes place at low temperatures below 250 °C.
AB - New iron-based intercalation superconductors Ax(C 2H8N2)yFe2- zSe2 (A = Li, Na) with Tc = 45 K have successfully been synthesized via intercalation of dissolved alkaline metal in ethylenediamine. The c-axis lengths of Ax(C2H 8N2)yFe2-zSe2 (A = Li, Na) are 20.74(7) Å and 21.9(1) Å, respectively, and are about 50% larger than that of KxFe2Se2, indicating that not only alkaline metal but also ethylenediamine is intercalated between the Se-Se layers of FeSe. It seems that the high-Tc of Ax(C2H8N2)yFe 2-zSe2 (A = Li, Na) is caused by the possible two-dimensional electronic structure due to the large c-axis length. Through the post-annealing in an evacuated glass tube, it has been found that Tc decreases with increasing post-annealing temperature and that deintercalation of EDA from the as-intercalated sample takes place at low temperatures below 250 °C.
KW - Alkaline metal
KW - Etylenediamine
KW - FeSe
KW - Intercalation
KW - Superconductivity
UR - http://www.scopus.com/inward/record.url?scp=84905275203&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84905275203&partnerID=8YFLogxK
U2 - 10.1016/j.physc.2014.01.007
DO - 10.1016/j.physc.2014.01.007
M3 - Article
AN - SCOPUS:84905275203
SN - 0921-4534
VL - 504
SP - 8
EP - 11
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
ER -