Jornada científica NanoFrontMag - 21 de junio de 2016 - IMDEA Nanociencia Grupo LBT-UAM Hermann Suderow

1. NUEVAS FRONTERAS DEL NANOMAGNETISMO FUNDAMENTAL Y APLICADO
4. Mejora de las propiedades magnéticas y eléctricas de los superconductores mediante la
fabricación de nanoestructuras hibridas
Objetivo 2: Control del campo magnético en nanoestructuras híbridas magnéticas/superconductoras

2. NUEVAS FRONTERAS DEL NANOMAGNETISMO FUNDAMENTAL Y APLICADO
4. Mejora de las propiedades magnéticas y eléctricas de los superconductores mediante la
fabricación de nanoestructuras hibridas
Objetivo 2: Control del campo magnético en nanoestructuras híbridas magnéticas/superconductoras
• ERC StG Pnicteyes, 1,7M€, PI Isabel Guillamón
• FIS2014-54498-R, 130k€, PI Hermann Suderow
• MDM-2014-0377, 160k€ Internal IFIMAC Project, Pis, Hermann Suderow and Alfredo Levy
• Nobu or Prof Nobuhiko Nishida, travel to Japan to see Toyota Museum …

3. • The size of the vortex core
• Pnictides or the iron age of superconductivity
Superconductivity

4. High power applications

5. Quantum computing

 i
e

6. 
 i
e0
Rotation
s
m1098.9
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



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n
m
h
n
d
m
d

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
l
lvs

27-
0
0
cmG1007.2
2
2
22m

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h
n
nd
e

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

l
Avp s


Superfluids
Superconductors
     
0
vS
0







 
m
ei

p
rr r

7. H
TTc
Hc1
Hc2
Hc
Meissner state
Mixed
state
Normal
phase
H
Meissner state
Mixed state
H
d
H(T)/50d(nm) 
r
s
2
nΨ 
H
J
J
Type II superconductors : high upper critical field + the vortex lattice
2
0
2
2

cH
 i
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E
E
EN

8. -2 -1 0 1 2
0.0
0.5
1.0
1.5
Normalizedconductance
Bias Voltage (mV)
-2 -1 0 1 2
0.0
0.5
1.0
1.5
Normalizedconductance
Bias voltage (mV)
0 mV 0.3 mV 0.5 mV
NbSe2
NbS2
Internal electronic structure of the vortex cores:
NbSe2 vs. NbS2
Superconducting density of states and vortex cores in NbS2
I. Guillamon, H. Suderow, S. Vieira and P. Rodiere
Phys Rev Lett, 101, 166407 (2008)

9. r
ns(r)
H(r)
r
E
|∆|
Vortex core shrinking with the magnetic field
Field dependence of the vortex core size
V.G. Kogan and N.V. Zhelezina,
Phys. Rev. B, 71, 134505 (2005).
d/dr  1/
r
E
|∆|
d/dr  1/H
r
E
|∆|
d/dr  1/H
r
E
|∆|
d/dr  1/(Hc20
IncreasingH

10. -Bi2Pd: Bi surface prepared by scotch method
140 nm
4.2 nm
1.7 nm
0.24 {1/A}
0 200
0
8
Z(A)
x(nm)
Pd
Bi
c
a
b
d=6.594 A
3.36 A
3.36A
12.97A

11. -Bi2Pd: single gap superconductor
-4 -2 0 2 4
0
1
2
NormalizedConductance
Bias Voltage (mV)
0 1 2 3 4 5
0.0
0.2
0.4
0.6
0.8
(meV)
T(K)
-2 -1 0 1 2
0
1
2
3
4
5
6
7
8
3.0 K
2.0 K
1.0 K
0.5 K
NormalizedTunnelingConductance
Bias Voltage (mV)
0.1 K
4.0 K
3.7 K
3.5 K
4.4 K
5.0 K
4.6 K
4.2 K

12. -Bi2Pd: hexagonal vortex lattice
1
0
50 mT5 mT 100 mT 200 mT 250 mT
300 mT 350 mT 400 mT 450 mT 500 mT
59 nm 59 nm 59 nm 59 nm 59 nm
59 nm84 nm84 nm110 nm220 nm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
147.66 mm
0.00 mm
1
0.01
1
0.03
1
0.1
1
0.2
1
0.4
1
0.5
1
0.6
1
0.7
1
0.3

13. -1 0 1
0
1
2
3
4
5
0 T
0.6T
0.5T
0.4T
0.3T
0.2T
Norm.Tunn.Cond.
Bias Voltage (mV)
0.1T
0.0 0.5
0.0
0.5
1.0
2H-NbS2
MgB2
2H-NbSe2
Single band
s-wave
-Bi2
Pd
mid
(r) B/B
c2
0.3 T
70 nm
-Bi2Pd: Magnetic field dependence of the intervortex density of states
MgB2
Kohen et al Appl. Phys. Lett.
86, 212503 (2005).

14. Vortex core shrinking with the magnetic field
Field dependence of the vortex core size
V.G. Kogan and N.V. Zhelezina,
Phys. Rev. B, 71, 134505 (2005).
r
E
|∆|
d/dr  1/H
r
E
|∆|
d/dr  1/H
r
E
|∆|
d/dr  1/(Hc20
0.3 T
70 nm
Calculations by V.G. Kogan
IncreasingH

15. Vortex core shrinking with the magnetic field
Field dependence of the vortex core size
V.G. Kogan and N.V. Zhelezina,
Phys. Rev. B, 71, 134505 (2005).
r
E
|∆|
d/dr  1/H
r
E
|∆|
d/dr  1/H
r
E
|∆|
d/dr  1/(Hc20
IncreasingH
80nm