Physics – Condensed Matter – Superconductivity
Scientific paper
2005-01-24
Solid State Comm. 133, 427 (2005)
Physics
Condensed Matter
Superconductivity
17 pages, 7 figures
Scientific paper
10.1016/j.ssc.2004.12.011
High-temperature superconductivity has been discovered in La2-xBaxCuO4 [1], a compound that derives from the undoped La2CuO4 crystallizing in the perovskite T-structure. In this structure oxygen octahedra surround the copper ions. It is common knowledge that charge carriers induced by doping in such an undoped antiferromagnetic Mott-insulator lead to high-temperature superconductivity [2- 4]. The undoped material La2CuO4 is also the basis of the electron-doped cuprate superconductors [5] of the form La2-xCexCuO4+y [6,7] which however crystallize in the so called T-prime-structure, i.e. without apical oxygen above or below the copper ions of the CuO2-plane. It is well known that for La2-xCexCuO4+y the undoped T-prime-structure parent compound cannot be prepared due to the structural phase transition back into the T-structure occuring around x ~ 0.05. Here, we report that if La is substituted by RE = Y, Lu, Sm, Eu, Gd, or Tb, which have smaller ionic radii but have the same valence as La, nominally undoped La2-xRExCuO4 can be synthesized by molecular beam epitaxy in the T-prime-structure. The second important result is that all these new T-prime-compounds are superconductors with fairly high critical temperatures up to 21 K. For this new class of cuprates La2-xRExCuO4, which forms the T-prime-parent compounds of the La-based electron doped cuprates, we have not been able to obtain the Mott-insulating ground state for small x before the structural phase transition into the T-structure takes place.
Alff Lambert
Krockenberger Y.
Manske Dirk
Naito Masashi
Noda Manabu
No associations
LandOfFree
New class of T-prime-structure cuprate superconductors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with New class of T-prime-structure cuprate superconductors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and New class of T-prime-structure cuprate superconductors will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-312318