Growth of $FeSe_x$ Superconducting Thin Films at Various Temperatures by PLD Technique

PLD법을 이용한 다양한 온도에서의 $FeSe_x$ 초전도 박막 성장

  • Jung, Soon-Gil (BK21 Physics Division and Department of Physics, Sungkyunkwan University) ;
  • Lee, N.H. (BK21 Physics Division and Department of Physics, Sungkyunkwan University) ;
  • Kang, W.N. (BK21 Physics Division and Department of Physics, Sungkyunkwan University) ;
  • Hwang, Tae-Jong (Department of Physics, Yeungnam University) ;
  • Kim, D.H. (Department of Physics, Yeungnam University)
  • Received : 2011.10.21
  • Accepted : 2011.12.10
  • Published : 2011.12.31

Abstract

We have fabricated $FeSe_x$ superconducting thin films at much different substrate temperatures of 430 and $610^{\circ}C$ on $Al_2O_3$(0001) substrates by using a pulsed laser deposition (PLD) technique. Superconducting transitions for both films were shown around 10 K, but their transition width and growth directions of grains were different. We found that superconducting tetragonal FeSe phases and non-superconducting hexagonal FeSe phases were coexisted in the sample grown at the low temperature of $430^{\circ}C$, whereas the hexagonal FeSe phase was decreased with increasing fabrication temperatures.

Keywords

References

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