Electronic Structure of New Iron Arsenide Superconductors

18 December 2008 (Thur), 3:30 pm - 5:00 pm

8F large seminar room, Sengen site

Dr. Zlata Pchelkina

Institute for Metal Physics, Ural Division, Russian Academy of Sciences

Electronic Structure of New Iron Arsenide Superconductors

In the beginning of 2008 the iron oxypnictides, a new family of superconductors, have been discovered starting with the famous work of H. Hosono group [1]. At present the several classes of these compounds are known: Re111 (Re=La,Ce,Pr,Nd,Sm) with parent compound LaO1-xFxFeAs and Tc about 40-55K; A122 (A=Ba,Sr) with parent system Ba1-xKxFe2As2 and Tc about 38K; Li1-xFeAs system with Tc=18K and Sr1-xLaxFFeAs compound with Tc=36K. It was also found that FeSe undergoes superconducting transition at temperature Tc=8K which can be increased to Tc=27K by applying high pressure.

In this talk an overview of different classes of FeAs based superconductors will be given, the basic physical properties and phase diagrams will be described. The results of electronic structure calculations for the parent compounds Re111 [2], Ba(Sr)122 [3], LiFeAs [4] and Ca(Sr)111 [5] will be presented.

[1] Y. Kamihara et al., J. Am. Chem. Soc. 130, 3296 (2008).

[2] I. A. Nekrasov, Z. V. Pchelkina, M. V. Sadovskii,Pis'ma Zh. Eksp. Teor. Fiz. 87, 647 (2008).

[3] I. A. Nekrasov, Z. V. Pchelkina, M. V. Sadovskii,Pis'ma Zh. Eksp. Teor. Fiz. 88, 155 (2008).

[4] I. A. Nekrasov, Z. V. Pchelkina, M. V. Sadovskii,Pis'ma Zh. Eksp. Teor. Fiz. 88, 621 (2008).

[5] I. A. Nekrasov, Z. V. Pchelkina, M. V. Sadovskii,Pis'ma Zh. Eksp. Teor. Fiz. 88, 777 (2008).

Dr. Igor Solovyev