bismuth based topological josephson junctions · li jorrit de boer bob de ronde university of...
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University of Twente, the Netherlands
Alexander Brinkman
Bismuth based topological
Josephson junctions
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Acknowledgements
University of Twente
Yingkai Huang
Anne de Visser
Erik van Heumen
Mark Golden
MartijnLankhorst
Chuan
LiJorritde Boer
Bobde Ronde
University of Amsterdam
Peter Schüffelgen
Daniel Rosenbach
Thomas Schäpers
Detlef Grüzmacher
Forschungszentrum Jülich
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Message of this talk
3D helical spin-momentum locking
of Dirac semimetal
- Topological transport
- 4p-periodic Andreev bound states
- Zeeman induced p-junction
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Non-Abelian anyons
“Qubits stored in topology are less likely
to be affected by their environment.”
Microsoft
Non-Abelian anyons
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Majoranas in superconductors?
Bogoliubov quasiparticles:
Needed for Majorana:
Zero energy state required
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Spin-momentum locking
Adv. Electr. Mater. 201900334 (2019)
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Topology and superconductivity
3D chiral p:3D s-wave:
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
PdTe2 type II Dirac semimetal
Dominant s-wave superconductor…
Phys. Rev. B 99, 014510 (2019)
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
NS S
NS S
TIS S
Calculations and figure
from Badiane,Meyer, HouzetStandard SNS:
Including interface barrier:
With topological interlayer:
Why topological Josephson junctions?
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Majorana manipulation on a surface
Fu & Kane, PRL 100, 096407 (2008)
Phase
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Advanced device fabrication
In situ electrode deposition by shadow mask technology
Selective area growth
enhanced IcRn
towards 1D
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Advanced device fabrication
Nature Nanotechnology 14, 821 (2019)
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Majoranas
1D Nanowires (InAs, InSb… )Strong evidence (Delft, Lund, Copenhagen)
SSS S
1D edges of 2D QSH (HgTe)Strong evidence (Würzburg)
S
3D bulk states (Dirac/Weyl semimetals)This talk
DSM
SS S
2D surface states of 3D topological insulators
(Bi2Se3, Bi2Te3, Bi1Sb1Te1Se2)First signatures
TI
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Sb doping concentration3%0%
3D Dirac semimetal Bi1-xSbx
“3D graphene”
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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Surface (111) of Bi1-xSbx
Angle resolved photoemission
spectroscopy (ARPES):
electrons: 1-2 x 1012 cm-2
holes: 1-2 x 1012 cm-2
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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Quantum oscillations of bulk holes
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Multiband magnetotransport
Electrons in the bulk Dirac cone:
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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Negative longitudinal
magnetoresistance (LMR)
3%✔ 4%✘
Chiral anomaly in Bi1-xSbx
Polarization of chirality:
Analogy pion decay:
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Monopole diffusion
Phys. Rev. B 99, 085124 (2019)
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Bi1-xSbx Josephson junctions
Bi1-xSbx
Nb
Nature Mater. 17, 875 (2018)
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Ballistic 500 nm Josephson junctions:
Bi1-xSbx Josephson junctions, x=0.03
Transparency = 0.9
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Observation of 4p-periodic supercurrent
Microwave irradiation:
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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From the critical frequency we obtain: I4p > 20% of Ic
Recovery of 2p-periodicity
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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Non-perpendicular trajectories
Towards single channel:
1. Quantization of tranverse
momentum
2. Including a magnetic layer
M. Snelder, M. Veldhorst, A.A. Golubov, A. Brinkman, Phys. Rev. B 87, 104507 (2013)
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
‘Majorana’ percentage
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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0 p
Giant Zeeman effect in Dirac cone
with g = 1000
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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S3 (accidental) SQUIDAsymmetric SQUID for current-phase relation
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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0 – pi transitions
Phys. Rev. Lett. 123, 026802 (2019)
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Conclusion and outlook
• Josephson supercurrent observed in several topological
Josephson junctions
• Largest Majorana signal in the 3D Dirac semimetal
• Thin films & gating needed
• Majorana character: Fu-Kane type experiment
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Outlook: Majorana vortex lattice
dimensionless self inductance of the loop
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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UNIVERSITY OF TWENTE.
Outlook: Majorana vortex lattice
Using local current pulses instead of flux biasing
Compatible with GHz rapid single flux quantum (RSFQ) technology?
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
31
UNIVERSITY OF TWENTE.
Outlook: Majorana vortex lattice
Using global current pulses and trap sites
IEEE CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), November 2019. Invited presentation 3-EO-TS-02l given at EUCAS, 1 – 5 September 2019, Glasgow, UK.
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