11-10 :: October 2011

nanotimes News in Brief

Graphene // Material with Graphene-Like Properties

© Text: HZDR T

ogether with colleagues from Korea, Dr. Frederik Wolff-Fabris from the Helmholtz-Zentrum

Dresden-Rossendorf (HZDR, Germany) has developed and analyzed a material which possesses physical properties similar to graphene. Its structure also resembles iron pnictides, i.e. high temperature superconductors, and it definitely has a promising future: Due to the position of the individual compo- nents in the Periodic Table of Elements, some of the atoms can simply be replaced by foreign atoms. This creates new materials which can be superconductive, magnetic, or behave like topological insulators.

Earlier this year, Dr. Jun Sung Kim came from South Korea to use HZDR’s Dresden High Magnetic Field Laboratory to analyze a number of material samples in high magnetic fields. For the first time ever, he and his colleague from Dresden, Dr. Frederik Wolff- Fabris, studied the metal SrMnBi2

and observed

something amazing: The material consisting of the three elements strontium, manganese, and bismuth behaves physically similar to the “magical material” graphene.

Due to its composition and the position of its ele- ments in the Periodic Table, SrMnBi2

permits sim-

ple and uncomplicated doping with foreign atoms. Inserting small amounts of foreign atoms alters the physical properties of a material. This might result

Image: The crystal structure of SrMnBi2 resembles iron

pnictides (green: bismuth; blue: strontium; red: manganese) © Marc Uhlarz/HZDR

in the creation of new magnets or supercon- ductors. SrMnBi2

is

currently also in the focus of other research groups; but only the use of ultra-high magnetic fields, such as those ge- nerated in the Dresden High Magnetic Field Laboratory, permitted these precise results. Later this year, Dr. Jun Sung Kim will return to Dresden to conduct additional experiments on SrMnBi2

41

with Dr. Wolff-Fabris.

Joonbum Park, G. Lee, F. Wolff-Fabris, Y. Y. Koh, M. J. Eom, Y. K. Kim, M. A. Farhan, Y. J. Jo, C. Kim, J. H. Shim, and J. S. Kim: Anisotropic Dirac Fermions in a Bi Square Net of SrMnBi2

No. 12, September 16, 2011, Article 126402 [5 pages], DOI:10.1103/PhysRevLett.107.126402: http://prl.aps.org/abstract/PRL/v107/i12/e126402

, In: Physical Review Letters, Vol. 107(2011),