Superconductivity in Bismuth Oxide Compounds Kitaoka Lab Takashi

Superconductivity in Bismuth Oxide Compounds Kitaoka Lab. Takashi MATSUMURA Mirza H. K. Rubel Angewandte Chemie International Edition Volume 53, Issue 14 B. A. Baumert Journal of Superconductivity, Vol. 8, No. 1, 1995 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 R. A. Schweinfurth et al. , Appl. Phys. Lett. 61 (1992)

Contents •

What is Superconductors u. Zero resistivity u. Perfect diamagnetism http: //allnewscience. blogspot. jp/2010/07/anti-gravity. html Superconductivity is caused by formation of an electron pair. Introduction

History of Superconductors 1975 Tcmax~12 K spin Ba. Pb. XBi 1 -XO 3 1988 TCmax~30 K Ba 1 -XKXBi. O 3 Spin + orbital phonon Introduction

Introduction

Bi-oxide compared with Cuprate Bi-oxide La. Sr. Cu. O 3 D 2 D Introduction

Bi-oxide compared with Cuprate Ｅｎｅｒｇｙ ? Ｅｎｅｒｇｙ (6 s)? (3 d)9 (5 d)10 Bi Cu Introduction

Valence skipping element Bi Bi 3+ [Xe](4 f)14(5 d)10 Bi 4+ [Xe](4 f)14(5 d)10 Bi 5+ [Xe](4 f)14(5 d)10 Bi 4+ Ｅｎｅｒｇｙ (6 s) Bi 3+ Bi 5+ Introduction

Ba. Bi. O 3 /

Ba. Bi. O 3 q In one dimension Bi 5+ -2 e Bi 3+ 0 e Bi 5+ Bi 3+ charge density wave(CDW) state R

Electron number is reduced Bi 3+ Bi 5+

In one dimension Bi 3+ Bi 5+ Bi 3+ Hole Doping Bi 3+ Bi 5+ Bi 3+ Bi 5+

In one dimension Bi 5+ Bi 3+ Hole Doping Bi 3+ Bi 5+ Bi 3+ Bi 5+

In one dimension Bi 5+ Bi 3+ Hole Doping Bi 3+ Bi 5+

Superconductivity

C D W ? S C

Crystal structure Bi 3+ Bi 5+

Crystal structure K concentration X x=0. 04 x=0. 4

Crystal structure x=0. 04 x=0. 4

After doping Bi 5+ Bi 3+ Bi 5+

After doping Bi 5+ Bi 3+ Bi 5+

After doping Bi 5+ Bi 3+ Bi 5+

After doping Bi 3+ Bi 5+ Bi 5+

Over doping Bi 5+ No electron Bi 5+ Cannot be superconductor

Double Perovskite structure

(BKBO) Similar Behavior!!

CDW

Summary •