Origin of the Metal-Insulator Transition of Indium Atom Wires on Si(111)

Abstract

As a prototypical one-dimensional electron system, self-assembled indium (In) nanowires on the Si(111) surface have been believed to drive a metal-insulator transition by a charge-density-wave (CDW) formation due to electron-phonon coupling. Here, our first-principles calculations demonstrate that the structural phase transition from the high-temperature 4x1 phase to the low-temperature 8x2 phase occurs through an exothermic reaction with the consecutive bond-breaking and bond-making processes, giving rise to an energy barrier between the two phases as well as a gap opening. This atomistic picture for the phase transition not only identifies its first-order nature but also solves a long-standing puzzle of the origin of the metal-insulator transition in terms of the x2 periodic lattice reconstruction of In hexagons via bond breakage and new bond formation, not by the Peierls instability-driven CDW formation.

arXiv comment5 pages, 4 figures + supplemental material

References in corpus (7)

• Structure determination of the indium-induced Si(111)-(4x1) reconstruction by surface x-ray diffraction
• Intrinsic magnetism at silicon surfaces
• Topological Solitons versus Non-Solitonic Phase Defects in Quasi-One-Dimensional Charge Density Wave
• Driving force of phase transition in Indium nanowires on Si(111)
• Grand canonical Peierls transition in In/Si(111)
• Atomic structure, energetics, and dynamics of topological solitons in Indium chains on Si(111) surfaces
• Equivalence of Electronic and Mechanical Stresses in Structural Phase Stabilization: A Case Study of Indium Wires on Si(111)

Cited by in corpus (6)

• Circular dichroism of emergent chiral stacking orders in quasi-one-dimensional charge density waves
• Grand canonical Peierls transition in In/Si(111)
• Excited state band mapping and momentum-resolved ultrafast population dynamics in In/Si(111) nanowires investigated with XUV based time- and angle-resolved photoemission spectroscopy
• Charge density wave melting in one-dimensional wires with femtosecond sub-gap excitation
• Band Structure Dynamics in Indium Wires
• Two-dimensional chiral stacking orders in quasi-one-dimensional charge density waves