Role of Stress in Thin Film Alloy Thermodynamics: Competition between Alloying and Dislocation Formation Academic Article uri icon

  •  
  • Overview
  •  
  • Research
  •  
  • Identity
  •  
  • Additional Document Info
  •  
  • View All
  •  

abstract

  • Using scanning tunneling microscopy (STM) and first-principles local-spin-density-approximation calculations to study submonolayer films of Co (1-c)Ag (c)/Ru(0001) alloys, we have discovered a novel phase-separation mechanism. When the Ag concentration c exceeds 0.4, the surface phase separates between a dislocated, pure Ag phase and a pseudomorphically strained Co(0.6)Ag (0.4) surface alloy. We attribute the phase separation to the competition between two stress relief mechanisms: surface alloying and dislocation formation. The agreement between STM measurements and our calculated phase diagram supports this interpretation.

authors

  • Thayer, GE
  • Ozolins, V
  • Schmid, AK
  • Bartelt, NC
  • Asta, M
  • Hoyt, Jeffrey
  • Chiang, S
  • Hwang, RQ

publication date

  • January 22, 2001