Berlin 2015 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 21: Superconductivity: Poster Session
TT 21.21: Poster
Monday, March 16, 2015, 15:00–18:00, Poster B
Scanning tunneling microscopy study on CaFe2As2 surface — •Philipp Ansorg1, Philip Willke1, Kalobaran Maiti2, Neeraj Kumar2, Sudesh Kumar Dhar2, Arumugum Thamizhavel2, and Martin Wenderoth1 — 1IV. Physikalisches Institut, Friedrich-Hund-Platz 1, 37077 Göttingen — 2Tata Institute of Fundamental Research Homi Bhabha Road, Colaba Mumbai-400 005, India
The discovery of high temperature superconductivity in cuprates leads to a great interest to examine also Fe-based systems. Superconductivity in the pnictide CaFe2As2 as a parent compound is induced by pressure or substitution of Fe by Co, Ni or other dopants.[1] Here we investigate the surface of CaFe2As2 by scanning tunneling microscopy and spectroscopy. Therefore the crystal [2] is cleaved under UHV conditions and cooled below the structural transition temperature of TS≈ 173K by LN2 or LHe. As found in similar systems [3] our STM data indicates a 2×1 surface reconstruction in the Ca layer at temperatures of both 6K and 77K. Furthermore anti-phase boundaries [4] along the 2×1 reconstruction can be observed.
[1] Y. Kamihara et al., J. Am. Chem. Soc. 128, 10012 (2006)
[2] G. Adhikary et al., J. Appl. Phys. 115, 123901 (2014)
[3] B. Saparov et al., Scientific Reports 4, 4120 (2014)
[4] K. Löser et al., Phys. Rev. B, 86, p. 085303 (2012)