Metallicity of Atomic Wires

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Metallicity of Atomic Wires I. N.
Yakovkin Institute of Physics, National Academy
of Sciences of Ukraine, Prospect Nauki 46, Kiev
03028, Ukraine. email yakov_at_iop.kiev.ua
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Fabrication of Nanowires by Laser-Focused Atomic
Deposition  
Laser standing wave propagates across a Si
surface, concentrating atoms into its nodes as
they deposit. The wires are spaced at exactly
half the laser wavelength.
Background A larger-range AFM image
Foreground 65 nm wide Cr wires
J.J. McClelland, R.E. Scholten, E.C. Palm, R.J.
Celotta, Science 262, 877 (1993).
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Stepped surfaces Templates for Atomic Wires
Fabrication of Fe and Gd wires
1D ferromagnets?!
F. Himpsel et al, J.Phys. Cond. Matt (2001)
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Electrons in one-dimensional systems
"In three dimensions, electronic properties of
metals are well described by the
Fermi-liquid-theory. In one-dimensional metallic
systems, the electron-electron interaction leads
to Luttinger liquid behavior".
"Electrons lose their identity and separate into
two quasiparticles with bosonic character, a
spinon that carries spin without charge, and a
holon that carries the positive charge of a hole
without its spin".  
Spincharge separation in a metallic Luttinger
liquid, calculated from first principles. An
ordinary energy band splits into two bands with
different group velocities which intersect at the
Fermi level.
"Spin-charge separation for a half-filled 1D
anti-ferromagnetic insulator"  
"1D Mott insulators cannot be described by the
Luttinger liquid theory, since this theory only
applies for systems without a gap in the charge
or spin excitation channel".
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Si(557)-Au and Si(553)-Au chain
structures
Band structure, viewed by multitedection
photoemission technique directly on a television
monitor.
Si(111)-Au
J. N. Crain, K. N. Altmann, C. Bromberger, S. C.
Erwin, A. Kirakosian, J. L. McChesney, J.-L. Lin,
F. J. Himpsel, PRL 2004
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Wilson NMT in a square Mg monolayer
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Zigzag Cs chain on GaAs surface
The image size is 7x7 nm
The self-assemble process results from Cs atoms
diffusing on the surface and searching out the
ends of existing Cs chains, which are
preferential sticking sites.     L. J.
Whitman, J. A. Stroscio, R. A. Dragoset, and R.
J. Celotta, PRL 66, 1338 (1991).
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Peierls' Transition
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Cs / GaAs Mott insulator?
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Atomic wires on metal surfaces
Ag on Pt(997) - highly stepped Pt(111) surface
F. Himpsel et al, J.Phys. Cond. Matt (2001)
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Gd wires in the second monolayer on Mo(112)
Losovyj,Yakovkin, Barrett, Komesu, and Dowben,
Surf. Sci. (2002)
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Au / TiO2 / Mo(112)
Mo(112)
CO oxidation rate
Chen and Goodman, Science (2004)
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Observation of the atomic wires Mg/Re(1010)
Medvedev and Yakovkin, Poverkhnost' (1982)
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Atomic wires on furrowed surfaces
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Lateral interaction between Sr adatoms along the
furrows on W(112) and Mo(112)
Dipole-dipole V 2m2/r3
Indirect V (A/r)Cos(2pkFrd)
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Monte Carlo simulations of order-disorder
transition in adsorbed films
W exp(-DE/kT)
T lt Tc
T gt Tc
I.N. Yakovkin, Surf. Sci. 282 (1993) 195
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Monte Carlo simulations p(1x5)Sr/Mo(112) and
p(1x7) Gd / W(112)
I.N. Yakovkin, Surf. Sci. 559/1 (2004) 29
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Mg-Mo(112) Wilson transition?..
Katrich, Klimov, Yakovkin, J. Elect. Spect. Rel.
Phenom. 68 (1994) 369
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Mg-Mo(112) Surface Photoeffect
Katrich, Klimov, Yakovkin, J. Elect. Spect. Rel.
Phenom. 68 (1994) 369
Katrich and Yakovkin, Ukr. Fiz. J. (1993)
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Wilson NMT in a linear Mg chain
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Mg-Mo(112) Transformations of band structure
along the furrows on increasing coverage - ARUPS
study
J. Zhang, McIlroy, Dowben, Phys. Rev. B (1994)
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Theory versus Experiment  
Band structure of the Mg overlayer on Mo(112)
along the surface furrows
J. Zhang, D.N. McIlroy and P.A. Dowben, Phys.
Rev. B 49 (1994) 13780 B 52 (1995) 11380. I.N.
Yakovkin, Surf. Sci. 488, 7 (2001) J.
Nanosci. Nanotechnol. 1, 357 (2001).
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Conclusions

• Atomic Wires do exist - Therefore they are not
  1D objects.
• Band structure is valid for atomic wires, and
  NMT can be reduced to Wilson transition in any
  case.
• Special electronic structure of Atomic Wires
  opens wide perspectives in development of new
  materials for nanoelectronics and catalysis - and
  deserves further investigations.