Influence of the spin-orbit coupling in the structural and electronic properties of Ir chains

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Influence of the spin-orbit coupling in the
structural and electronic properties of Ir chains

• Víctor M. García Suárez1, Lucas
  Fernádez-Seivane2,
• Colin J. Lambert1 and Jaime Ferrer2
• 1Physics Department, Lancaster University
• 2Departamento de Física, Universidad de Oviedo

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• Simulations of monoatomic chains
• - Ab initio method
• - Au, Pt and Ir chains
• Infinite iridium chains
• - Structural and electronic properties
• - Transport properties

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Simulations of monoatomic chains
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Simulations of monoatomic chains

• Smeagol (DFT Hamiltonian from SIESTA)
• - Scattering problem
• - Density matrix and transmission

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Simulations of monoatomic chains

• Monoatomic chains
• - Conductance in the last
• plateau between 2.2 and
• 0.9 G0
• - Oscillations with
• negative slope (Pt Ir)
• - Distance between peaks
• 2.3 Å

Smit et al. PRL 91, 076805 (2003)
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Simulations of monoatomic chains
Zigzag
Linear

• Infinite chains
• - Local zigzag
• minimum
• - N. of channels
• halved in the
• zigzag case
• compared to
• the linear case

PRL 95, 256804 (2005)
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Infinite iridium chains
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Infinite iridium chains

• Structural configurations
• linear, zigzag and ladder

linear
zigzag
ladder
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Infinite iridium chains

• Magnetic configurations
• high and low spin

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Infinite iridium chains

• Spin-orbit coupling effects

Different spin orientations depending on dz
90, 00
00, 00
90, 90
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Infinite iridium chains

• The magnetic modulus also changes

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Infinite iridium chains

• Transmission channels in the
• spin-polarized case

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Infinite iridium chains

• Transmission channels with spin-orbit
• - Linear chains

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Infinite iridium chains

• Transmission channels with spin-orbit
• - Linear vs zigzag chains in the linear regime

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Infinite iridium chains

• Transmission channels with spin-orbit
• - Zigzag chains

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Infinite iridium chains

• Band structure

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Infinite iridium chains

• Transmission channels in zigzag chains
• Spin polarized vs spin-orbit

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• Conclusions
• - Zigzag and ladder chains are more stable
• than linear chains
• - Different magnetic configurations as a
• consequence of the spin-orbit coupling
• - The inclusion of the spin-orbit alters
• dramatically the number of channels

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