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Transcript of NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc....
![Page 1: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/1.jpg)
NMR study on bismuth oxide superconductor BaPbxBi1-xO3
H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705
Kitaoka Lab.Takashi MATSUMURA
K.Kumagai.et,al Physica C 274 (1997) 209-220
![Page 2: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/2.jpg)
Contents
• Introduction• NMR,NQR• Result
137Ba spectrum137Ba ・ 135Ba T1
• Summary
![Page 3: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/3.jpg)
TCmax~30K
Ba1-XKXBiO3
1988
spin
Spin +
orbital
phonon
BaPbXBi1-XO3
Tcmax~12K
1975
History of Superconductors
Introduction
Valence skipper?
![Page 4: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/4.jpg)
O (1s)2(2s)2(2p)4
O2- (1s)2(2s)2(2p)6
Bi [Xe](4f)14(5d)10(6s)2(6p)3
Bi3+ Bi5+
[Xe](4f)14(5d)10(6s)2(6p)0
[Xe](4f)14(5d)10(6s)0(6p)0
Skipping (ns)1 state Valence skipper
結晶化学入門 遠藤忠 他 講談社サイエンティフィック、 wikipedia
Valence skipper
Introduction
Anion
Cation
closed-shell structure
stable structure
Bi4+ [Xe](4f)14(5d)10(6s)1(6p)0 unstable structure
![Page 5: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/5.jpg)
Negative U
Introduction
6s0
6s1
6s2
: Energy of electron
US: Coulomb interaction
<E1
Attraction
US<0
![Page 6: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/6.jpg)
Candidates for Valence skipper SC
Introduction
Valence skipping effect?
Nb1-xTaxSe3 (Nb3+,Nb5+)
AgSnSe2 (Sn2+,Sn4+)
Pb1-xTlxTe (Tl1+,Tl3+)
BKBO,BPBO (Bi3+,Bi5+)
-Na0.33V2O3 (V3+,V5+)・・・
・・・
![Page 7: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/7.jpg)
Mother compound BaBiO3
Ba
Bi3+
Bi5+
O
Ba
Bi3+
Bi5+
O
Perovskite structure
BaPbxBi1-xO3
Different valence Bi
![Page 8: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/8.jpg)
Ba
Bi3+
Bi5+
O
Ba
Bi3+
Bi5+
O
Mother compound BaBiO3
Ba2+¿¿ O2−×3
Bi4+¿¿
Bi3+¿ ¿ Bi5+¿ ¿/
BaPbxBi1-xO3
![Page 9: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/9.jpg)
Superconductivity of BaPbxBi1-xO3
BaPbxBi1-xO3
sc
BaBiO3
Bi [Xe](4f)14(5d)10(6s)2(6p)3 Pb [Xe](4f)14(5d)10(6s)2(6p)2 Hole doping
BaPb0.5Bi0.5O3 BaPbO3
Hole dopingCDW state
CDW
stat
e
![Page 10: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/10.jpg)
Samples
sc
Hole doping
BaPbxBi1-xO3
x=0.64 Semiconductor
x=0.75 Superconductor
x=0.91 Metallic
0.64 0.91
BaBiO3
CDW
stat
e
BaPbxBi1-xO3
![Page 11: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/11.jpg)
Ex. I=1/2
I=1/2
H0 = 0 H0≠0m=+1/2
m=-1/2
g Hℏ 0
Zeemann splitting
ω= g H0
NMR (Nuclear Magnetic Resonance) 核磁気共鳴 γ (gyromagnetic ratio) 磁気回転比
Nuclear Magnetic Resonance
𝐻 0 Zeeman interaction
tH cos1
NMR,NQR
NM
R In
tens
ity [a
.u.]
Frequency,H0ω,H0
![Page 12: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/12.jpg)
NMR,NQR
NQ
R In
tens
ity [a
.u.]
FrequencyνQ
Nuclear Quadrupole Resonance
Ex. Ba I=3/2 +
+
+
+m=±1/2
m=±3/2
222
3)12(4
IIII
qQeΗ zQ
hνQ
tH cos1
quadrupole interaction
![Page 13: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/13.jpg)
137Ba NQR Spectrum of x=0.91: Metallic
=13MHz
=10.9, 1
(T=1.6K)
Spectrum
![Page 14: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/14.jpg)
Nuclear Magnetic Resonance
∝𝜈Q 2
Ex. Ba I=3/2
NMR,NQR
=9MHzω~42MHz
NM
R In
tens
ity
=0.4
=0
ω
EFG: 電荷分布
Real, broadening
Ideal
=1
Real, broadening
Ideal
ω
![Page 15: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/15.jpg)
Mother compound BaBiO3
Ba
Bi3+
Bi5+
O
Ba
Bi3+
Bi5+
O
Perovskite structure
BaPbxBi1-xO3
Rotation
![Page 16: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/16.jpg)
Ba site: tetragonal
0
1
Spectrum
(1,0,0)
VXXVXX
VZZ VZZ
VYYVYY
![Page 17: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/17.jpg)
Spectrum
0
1
Ba site: orthorhombic
1 : tetragonal1 : orthorhombic
Crystal structure Spectrum shape
![Page 18: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/18.jpg)
137Ba NMR Spectrum of x=0.91: Metallic
x=0.91 Metallic =10.9
1
Spectrum
20K One componenttetragonal
![Page 19: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/19.jpg)
137Ba NQR Spectrum of x=0.64: Semiconductor
=12.5MHz,14MHz
=10.9, =0.9 =12.5, =0.65
(T=1.6K)
two two Spectrum
![Page 20: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/20.jpg)
137Ba NMR Spectrum of x=0.64: Semiconductor
=12.5= 0.65
=10.9=0.9
40%
60%
+
=10.9=0.9
=12.5= 0.65
Spectrum
20K Two components
tetragonal
orthorhombic
![Page 21: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/21.jpg)
Two components
=14.3= 0.4
=11.5=0.8
30%
70%
+=11.5=0.8
=14.3= 0.4
137Ba NMR Spectrum of x=0.75: Superconductor
Spectrum
20K
tetragonal
orthorhombic
![Page 22: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/22.jpg)
(1) (1)
Part of 1
Tetragonal phasex=0.91 Metallic
x=0.64 Semiconductor
x=0.75 Superconductor
Tetragonal phase+
Orthorhombic distortion
Temperature vs
Tetragonal phase+
Orthorhombic distortion
Spectrum
T<350K
T<350K
Whole temperature
Tetra
Tetra
Tetra
Ortho
Ortho
![Page 23: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/23.jpg)
m=+1/2
m=-1/2
H0
timet
M
M(t) = M(∞)[1- exp(-t/T1)]
Thermal equilibrium state
M = M(∞)Relaxation
M = M( t)
Exited state
M = M(0) = 0
t < 0 t = 0 t > 0tH cos1
0
Ex. I=1/2
Ba T1
Electronic spin, etc.
Nuclear magnetic relaxation rate (T1-1)
![Page 24: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/24.jpg)
Ba T1
137Ba/135Ba-NMR
T1Q-1T1M
-1
Valence skipping fluctuation?
T1-1=T1M
-1+T1Q-1
∝𝛾 2 ∝(𝑒𝑄)2
Nuclear magnetic relaxation rate (T1-1)
![Page 25: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/25.jpg)
Nuclear magnetic relaxation rate (T1-1)
x=0.91 Metallic
x=0.75 Superconductorx=0.64 Semiconductor
Ba T1
smalllarge
Ea
![Page 26: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/26.jpg)
Samples
sc
Hole doping
BaPbxBi1-xO3
x=0.64 Semiconductorx=0.75 Superconductorx=0.91 Metallic
0.64 0.91
BaBiO3
CDW
fluctuationsmalllarge
CDWfluctuation?
Ba T1
![Page 27: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/27.jpg)
Pair hopping
Bi Bi
Bi Bi
Pb Pb
Pb PbPb Pb
Pb Pb
Pb PbPb Pb
Ba
Bi3+
Bi5+
O
Ba
Bi3+
Bi5+
O
BaPbxBi1-xO3
x=0.75
Pair hopping
![Page 28: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/28.jpg)
Bi (6S) state
Pair hopping
Ba
Bi3+
Bi5+
O
Ba
Bi3+
Bi5+
O
BaPbxBi1-xO3
x=0.75
Pair hopping
![Page 29: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/29.jpg)
Bi (6S) state
Pair hopping
Ba
Bi3+
Bi5+
O
Ba
Bi3+
Bi5+
O
BaPbxBi1-xO3
x=0.75
Negative U
Pair hopping
![Page 30: NMR study on bismuth oxide superconductor BaPb x Bi 1-x O 3 H. Matsuura and K. Miyake, J. Phys. Soc. Jpn. 81 (2012) 113705 Kitaoka Lab. Takashi MATSUMURA.](https://reader035.fdocuments.net/reader035/viewer/2022062518/56649edb5503460f94bebb1e/html5/thumbnails/30.jpg)
Summary
• Superconductivity and a change of the structure are in a close relation.
• Nuclear relaxation mechanism was determined by charge fluctuations.
• The superconductivity in BPBO may be mediated by the valence skipping effect.