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Superconducting properties of oxygenated La2−xSrxCuO4+y (0≤x≤0.06)
Physica C 185-189 (1991) 577-578 North-Holland
SUPERCONDUCTING PROPERTIES OF OXYGENATED La2-.Sr~CuO4.y
Y.
Fujiwara
~,
A.
Hayashl ",
Y.
Ueda ",
K.
Shibutanl
b,
R.
(0Zx!0.O6)
0gawa b
Institute for Solid State Pltyslcs, Univ. of Tokyo, 7-22-1, Roppongi, Mlnato-ku, Tokyo 106, Japan b Kobe Stecl i.td., 1-5-5, Takatsukadai, Nishi-ku, Kobe 6 5 1 - 2 2 , J a p a n .
Oxygenated La2_~Sr~CuO4.y (O
powders 1.
INTRODUCTION The
compounds
sized
in
La=_~Sr~CuOa
flowing
oxygen
superconductivity
in
O.OBcx
and
l.a~Cue~.
a
the
Is
ottler
shows sen
first
Is
conducting
tion
a mixed
On
La2Cu()4.y
near
neutron
this
Po~=3GO Kobe cooled
in
release
of
The
separa-
ambient
atmo:;-
paper,
we of
report
the
two
a
Eig.
l.a2-~Sr~CuO~.~
The solid
starting state of
renctlon
La~03,
were
from appropriate
SrCC:,
and
CuO.
The
0921-4534/91/$03.50 © 199! - Elsevier Science Publishers B.V.
of
1-5
a
were
t.~
was
mA.
samples
low-field
flux
the
meas-
method, As
shown
sLv,'.'~,d all
zero
samoles
exclusion,
oxygenated
~h;,:h
l,a~ ~Sr,,C;104.,
diffraction
monochromatlc
made
using
with
a closed-cycle
a
Each o x y g e n a t e d 10 K t o a
~sing
a bu~-k s u p e r c o e d u c t o c .
with
prepared
,Jnder
a,ld
probe
Furthermore,
Pounder X - r a y
(x<0.06).
materials
all
that
h
48
pressure.
current
1,
for
prior
DC f o u r
showed
superconducting
6 30T.
resistivity
resistance.
is
for
system
electrical
which
phase
applied
tbe~,e
"C
oxyg.~nated
furnace
24
heated
then 900
by a standard
l.a2CuO~.,,o,
in
the
for
TP.e p r o c -
at
GO0 "C
02-1lip
"C and
tw]oo,
annealed
at
at:m
SLe(:t
900
air.
"l'h(~.~e ~ a m r ) l e ~ w e r e
supplying
the
in
repo~tod
super-
of
EXPERIMENTAL AND RESUI,TS
mixture
h.
at
pelletized, 48 h
were
oxygen
K under
behavior
oxygenated
by
was
pellet.~
confirm
phase
2.
10(),'.) ' C f o r
oxygenated
phere. In
at ess
ground,
excess
a macroscopic 320
by
¢:ateined
then
ured
with
insulating from
Jorgen-
the
phase
La2CuO.,.y
the
result
that
of
compound,
insulator.
showed 2
the
range
oxygenated
diffraetion
l.a~CuO4.y
and
the
superconductivity'.
al.
powder
show
parent
typical
hand,
the et
the
synthe-
were
h,
be
nearly
All rights reserved.
Mae
CuKa
me:t.~ureme.qls radiation
were
MXP ' ~
system
Science helium
sample
was
refrigerator. identlf~_ed
a mixture
of
t~o
identical
structure
phases but
at
~ith ".he,
Y. Fujiwara et a£ / Superconducting properties of oxygenated La 2.xSrxCuO4, y (0
578
0.8
0.04
I
I
o x = 0.02 ~ x = 0.06
f~.
I
400
• x=O.O0
O4O
0.03
0.6
,~ 0.02
0.4
00{ X=
t~
o ~
o
s
o
0.01
0.2
0
& 6
0.06{
o
o
_A_,.,
0.0( 0
1°"°2{_.A___y
?
20
I,
I
40
I
60
80
I
~)00.0
T (K)
Resistivity oxygenated 0.02~ 0.06.
different
the
the
040
curves for with x=O.O,
strain.
and 400
coexistence
Figure
reflections of
two
seen.
400
reflections
phases
lap
each
phases
other,
have
the
two
indicating
almost
For La=CuO4.y,
that
seme value
the
I
I
69
70
,
I
71
from
FIGURE 2 The 040 and 400 reflections of La2-xSr~CuO4,y. (A), (B), and (C) for oxygenated sampies. (a), (b), and (c) for samples prepared in flowing oxygen. The arrows indicate the 040 reflections of" e a c h s e c o n d phase.
orthorhom-
b i c p h a s e s can be c l e a r l y of
"
20 (deg)
FIGURE 1 temperature ~Sr~Cu04.~
orthorhomhlc
2 shows which
vs l.a2
~
REFERENCES
overthe
of
lattice
The
two
1.
O. I ) e m a z c a u , F . T r e s s e , Th. Plante, B. C h e v a l i e r , ,I. E t o u r n e a u , C. M i c h e l , M. I l e r v i e u , 13. R a v e a u , P . l . e J a y , A. S u l p i c e , a n d R. T o u r n l e r , Physica C153-155 (1988) 824.
2.
J.I). ,]orgcnscn B. D a b r o w s k i , Shiyou Pei, D.G. llinks, I.. S o d e r h o l m , B. "viorosin, J.E. Schirber, I'~.L. v e n t u r i ni, and I).S. Clncley. Phys. Rev. !]38 (1988) 1 1 3 3 7 .
a-axis.
parameters
of the two phases were in good agreement with those r e p o r t e d by Jorgensen e t a ] 2 The phase with the s m a l l e r orthorhombic strain
was
prepared (a).
(b),
that
thls
the
not observed
in
flowing
and
oxygen (see F i g . 2
(c)),
phase
is
which
indicates
responsible
superconductivlty
La2-xSr~CuO4.y.
in the sample
of
for
oxygenated
SUPERCONDUCTING PROPERTIES OF OXYGENATED La2-.Sr~CuO4.y
Y.
Fujiwara
~,
A.
Hayashl ",
Y.
Ueda ",
K.
Shibutanl
b,
R.
(0Zx!0.O6)
0gawa b
Institute for Solid State Pltyslcs, Univ. of Tokyo, 7-22-1, Roppongi, Mlnato-ku, Tokyo 106, Japan b Kobe Stecl i.td., 1-5-5, Takatsukadai, Nishi-ku, Kobe 6 5 1 - 2 2 , J a p a n .
Oxygenated La2_~Sr~CuO4.y (O
powders 1.
INTRODUCTION The
compounds
sized
in
La=_~Sr~CuOa
flowing
oxygen
superconductivity
in
O.OBcx
and
l.a~Cue~.
a
the
Is
ottler
shows sen
first
Is
conducting
tion
a mixed
On
La2Cu()4.y
near
neutron
this
Po~=3GO Kobe cooled
in
release
of
The
separa-
ambient
atmo:;-
paper,
we of
report
the
two
a
Eig.
l.a2-~Sr~CuO~.~
The solid
starting state of
renctlon
La~03,
were
from appropriate
SrCC:,
and
CuO.
The
0921-4534/91/$03.50 © 199! - Elsevier Science Publishers B.V.
of
1-5
a
were
t.~
was
mA.
samples
low-field
flux
the
meas-
method, As
shown
sLv,'.'~,d all
zero
samoles
exclusion,
oxygenated
~h;,:h
l,a~ ~Sr,,C;104.,
diffraction
monochromatlc
made
using
with
a closed-cycle
a
Each o x y g e n a t e d 10 K t o a
~sing
a bu~-k s u p e r c o e d u c t o c .
with
prepared
,Jnder
a,ld
probe
Furthermore,
Pounder X - r a y
(x<0.06).
materials
all
that
h
48
pressure.
current
1,
for
prior
DC f o u r
showed
superconducting
6 30T.
resistivity
resistance.
is
for
system
electrical
which
phase
applied
tbe~,e
"C
oxyg.~nated
furnace
24
heated
then 900
by a standard
l.a2CuO~.,,o,
in
the
for
TP.e p r o c -
at
GO0 "C
02-1lip
"C and
tw]oo,
annealed
at
at:m
SLe(:t
900
air.
"l'h(~.~e ~ a m r ) l e ~ w e r e
supplying
the
in
repo~tod
super-
of
EXPERIMENTAL AND RESUI,TS
mixture
h.
at
pelletized, 48 h
were
oxygen
K under
behavior
oxygenated
by
was
pellet.~
confirm
phase
2.
10(),'.) ' C f o r
oxygenated
phere. In
at ess
ground,
excess
a macroscopic 320
by
¢:ateined
then
ured
with
insulating from
Jorgen-
the
phase
La2CuO.,.y
the
result
that
of
compound,
insulator.
showed 2
the
range
oxygenated
diffraetion
l.a~CuO4.y
and
the
superconductivity'.
al.
powder
show
parent
typical
hand,
the et
the
synthe-
were
h,
be
nearly
All rights reserved.
Mae
CuKa
me:t.~ureme.qls radiation
were
MXP ' ~
system
Science helium
sample
was
refrigerator. identlf~_ed
a mixture
of
t~o
identical
structure
phases but
at
~ith ".he,
Y. Fujiwara et a£ / Superconducting properties of oxygenated La 2.xSrxCuO4, y (0
578
0.8
0.04
I
I
o x = 0.02 ~ x = 0.06
f~.
I
400
• x=O.O0
O4O
0.03
0.6
,~ 0.02
0.4
00{ X=
t~
o ~
o
s
o
0.01
0.2
0
& 6
0.06{
o
o
_A_,.,
0.0( 0
1°"°2{_.A___y
?
20
I,
I
40
I
60
80
I
~)00.0
T (K)
Resistivity oxygenated 0.02~ 0.06.
different
the
the
040
curves for with x=O.O,
strain.
and 400
coexistence
Figure
reflections of
two
seen.
400
reflections
phases
lap
each
phases
other,
have
the
two
indicating
almost
For La=CuO4.y,
that
seme value
the
I
I
69
70
,
I
71
from
FIGURE 2 The 040 and 400 reflections of La2-xSr~CuO4,y. (A), (B), and (C) for oxygenated sampies. (a), (b), and (c) for samples prepared in flowing oxygen. The arrows indicate the 040 reflections of" e a c h s e c o n d phase.
orthorhom-
b i c p h a s e s can be c l e a r l y of
"
20 (deg)
FIGURE 1 temperature ~Sr~Cu04.~
orthorhomhlc
2 shows which
vs l.a2
~
REFERENCES
overthe
of
lattice
The
two
1.
O. I ) e m a z c a u , F . T r e s s e , Th. Plante, B. C h e v a l i e r , ,I. E t o u r n e a u , C. M i c h e l , M. I l e r v i e u , 13. R a v e a u , P . l . e J a y , A. S u l p i c e , a n d R. T o u r n l e r , Physica C153-155 (1988) 824.
2.
J.I). ,]orgcnscn B. D a b r o w s k i , Shiyou Pei, D.G. llinks, I.. S o d e r h o l m , B. "viorosin, J.E. Schirber, I'~.L. v e n t u r i ni, and I).S. Clncley. Phys. Rev. !]38 (1988) 1 1 3 3 7 .
a-axis.
parameters
of the two phases were in good agreement with those r e p o r t e d by Jorgensen e t a ] 2 The phase with the s m a l l e r orthorhombic strain
was
prepared (a).
(b),
that
thls
the
not observed
in
flowing
and
oxygen (see F i g . 2
(c)),
phase
is
which
indicates
responsible
superconductivlty
La2-xSr~CuO4.y.
in the sample
of
for
oxygenated