Investigation of TiO{sub x} barriers for their use in hybrid Josephson and tunneling junctions based on pnictide thin films

Journal Article · Fri Feb 28 04:00:00 EST 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4863172· OSTI ID:22278014

Monecke, M.; Schmidt, S.; Schmidl, F.; Tympel, V.; Engelmann, J.; Kurth, F.; Iida, K.; Holzapfel, B. ^[1]; Haindl, S. ^[2]; Mönch, I. ^[3]

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1. Institute for Metallic Materials, IFW Dresden, Helmholtzstrasse 20, 01171 Dresden (Germany)
2. Institute for Solid State Research, IFW Dresden, Helmholtzstrasse 20, 01171 Dresden (Germany)
3. Institute for Integrative Nanosciences, IFW Dresden, Helmholtzstrasse 20, 01171 Dresden (Germany)

We tested oxidized titanium layers as barriers for hybrid Josephson junctions with high I{sub c}R{sub n}-products and for the preparation of junctions for tunneling spectroscopy. For that we firstly prepared junctions with conventional superconductor electrodes, such as lead and niobium, respectively. By tuning the barrier thickness, we were able to change the junction's behavior from a Josephson junction to tunnel-like behavior applicable for quasi-particle spectroscopy. Subsequently, we transferred the technology to junctions using Co-doped BaFe{sub 2}As{sub 2} thin films prepared by pulsed laser deposition as base electrode and evaporated Pb as counter electrode. For barriers with a thickness of 1.5 nm, we observe clear Josephson effects with I{sub c}R{sub n}≈90 μV at 4.2 K. These junctions behave SNS'-like (SNS: superconductor-normal conductor-superconductor) and are dominated by Andreev reflection transport mechanism. For junctions with barrier thickness of 2.0 nm and higher, no Josephson but SIS'- (SIS: superconductor-insulator-superconductor) or SINS'-like (SINS: superconductor-normal conductor-insulator-superconductor) behavior with a tunnel-like conductance spectrum was observed.

• OSTI ID: 22278014
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 115; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BARIUM COMPOUNDS
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
ENERGY BEAM DEPOSITION
IRON ARSENIDES
JOSEPHSON JUNCTIONS
LASER RADIATION
LAYERS
NIOBIUM
PULSED IRRADIATION
QUASI PARTICLES
SUPERCONDUCTORS
THIN FILMS
TITANIUM
TITANIUM OXIDES
TUNNEL EFFECT