Role of defects in
two-dimensional phase transitions: An STM study of the Sn/Ge(111)
system
A. V. Melechko, J. Braun,
H. H. Weitering, and E. W. Plummer
Physical Review B, 2000. 61(3): p. 2235-2245.
Abstract
The influence
of Ge substitutional defects and vacancies on the (sqrt[3] x
sqrt[3])-->(3
x 3) charge-density wave phase transition in the alpha phase
of Sn on Ge(111) has been studied using a variable-temperature scanning
tunneling microscope. Above 105 K, Ge substitutional defects stabilize
regions with (3 x 3) symmetry that grow with decreasing
temperature and can be described by a superposition of exponentially
damped waves. At low temperatures, T <~ 105 K
defect-defect density-wave-mediated interactions force an alignment of
the defects onto a honeycomb sublattice that supports the
low-temperature (3 x 3) phase. This defect-mediated phase
transition is completely reversible. The length scales involved in this
defect-defect interaction dictate the domain size ( ~ 104
Å 2).
©2000 The
American Physical Society
URL:
http://link.aps.org/abstract/PRB/v61/p2235
DOI: 10.1103/PhysRevB.61.2235
PACS: 68.35.Rh, 68.35.Bs, 71.45.Lr, 72.10.Fk
Learn
more by visiting pages of researchers working in
this area:
Luca Ottaviano
Roger Uhrberg
José Ortega Mateo
Phase transitions in wikipedia
Sn/Ge(111) image gallery
Ph.D.
Dissertation
(10 Mb pdf)
Ward Plummer
Hanno Weitering
Interactive Phase Transitions on lattices with Java applets
