In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 111, No. 1 ( 2014-01-07), p. 63-68
Abstract:
Several superconducting transition temperatures in the range of 30–46 K were reported in the recently discovered intercalated FeSe system (A 1- x Fe 2- y Se 2 , A = K, Rb, Cs, Tl). Although the superconducting phases were not yet conclusively decided, more than one magnetic phase with particular orders of iron vacancy and/or potassium vacancy were identified, and some were argued to be the parent phase. Here we show the discovery of the presence and ordering of iron vacancy in nonintercalated FeSe (PbO-type tetragonal β -Fe 1- x Se). Three types of iron-vacancy order were found through analytical electron microscopy, and one was identified to be nonsuperconducting and magnetic at low temperature. This discovery suggests that the rich-phases found in A 1- x Fe 2- y Se 2 are not exclusive in Fe-Se and related superconductors. In addition, the magnetic β -Fe 1- x Se phases with particular iron-vacancy orders are more likely to be the parent phase of the FeSe superconducting system instead of the previously assigned β -Fe 1+ δ Te.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.1321160111
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
2014
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12