Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations spatially coexist with antiferromagnetism.


(left) Scanning tunneling microscopy (STM) image (perspective view) of a heterostructure interface consisting of two non-superconducting materials, namely a topological insulator as substrate and an ultrathin film of iron-telluride grown on top. The unit-cell high layer of FeTe exhibits simultaneously bi-collinear antiferromagnetic order as revealed by spin-resolved STM (right) and superconducting properties at the same location as measured by the spectroscopic STM mode (bottom).

Image source: S. Manna and R. Wiesendanger, University of Hamburg, Germany

Most remarkably, the team headed by Professor Roland Wiesendanger was able to observe this coexistence for the first time on the atomic scale using spin-resolved scanning tunneling microscopy and spectroscopy.

These exciting results, reported in today’s issue of Nature Communications, challenge the understanding of the nature of electronic Cooper-pairing in iron based superconductors, which is the class of superconducting materials most heavily studied in recent years.

The discovery of high-temperature superconductivity in iron based compounds initiated numerous studies on the relationship between magnetic and superconducting order by various experimental and theoretical methods. Moreover, the unusual enhancement of the superconducting transition temperature by interface effects, as reported a few years ago for the case of ultrathin FeSe films grown on SrTiO₃ substrates, created additional excitement in the scientific community. Interestingly, in contrast to FeSe, the related compound FeTe does not exhibit a superconducting phase, but shows antiferromagnetic ordering up to a critical temperature of about 70 K.

Therefore, it is even more remarkable that ultrathin FeTe films grown on non-superconducting Bi₂Te₃ substrates show clear signs of superconductivity. The coupling of a superconductor to a topological insulator such as Bi₂Te₃, as realized in the experiments by the Hamburg group, is not only interesting from a fundamental research point of view:

It has been theoretically predicted that such hybrids can host Majorana Fermions in the center of superconducting vortex cores formed upon the application of an external magnetic field. Majorana Fermions are currently widely explored in different research disciplines as a new platform for fault-tolerant quantum computation. The fascinating results obtained for FeTe/Bi₂Te₃ heterostructures can therefore be regarded as an important step towards the experimental realization of such dreams.

Original publication:
Interfacial superconductivity in a bi-collinear anti-ferromagnetically ordered FeTe monolayer on a topological insulator,
S. Manna, A. Kamlapure, L. Cornils, T. Hänke, E. M. J. Hedegaard, M. Bremholm, B. B. Iversen, Ph. Hofmann, J. Wiebe, and R. Wiesendanger,
Nature Communications, online publication: 17.01.2017,
DOI: 10.1038/NCOMMS14074.

Further related work in the recent literature:
Reorientation of the diagonal double-stripe spin structure at Fe1+yTe bulk and thin film surfaces,
T. Hänke, U. R. Singh, L. Cornils, S. Manna, A. Kamlapure, M. Bremholm, E. M. J. Hedegaard, B. B. Iversen, Ph. Hofmann, J. Hu, Z. Mao, J. Wiebe, and R. Wiesendanger,
Nature Communications 8, 13939 (2017), online publication from 06.01.2017.

Primary research funding:
We are particularly grateful for research funding by the European Research Council in the framework of the ERC Advanced Grant ASTONISH.

Additional information:
Prof. Dr. Roland Wiesendanger
University of Hamburg
Jungiusstr. 9A/11A
D-20355 Hamburg
Germany
E-Mail: wiesendanger@physnet.uni-hamburg.de
Phone.: +49- 40 - 4 28 38 - 52 44

Weitere Informationen:

http://www.nanoscience.de
http://www.nanoscience.de/astonish

Heiko Fuchs | idw - Informationsdienst Wissenschaft

More articles from Materials Sciences:

nachricht Contacting the molecular world through graphene nanoribbons
19.02.2018 | Elhuyar Fundazioa

nachricht When Proteins Shake Hands
19.02.2018 | Friedrich-Schiller-Universität Jena

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Contacting the molecular world through graphene nanoribbons

19.02.2018 | Materials Sciences

When Proteins Shake Hands

19.02.2018 | Materials Sciences

Cells communicate in a dynamic code

19.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>