Mechanical properties of clusters in quasicrystal approximants: The example of the 1/1 Al-Cu-Fe approximant

Abstract

Quantum-mechanical molecular dynamics have been used to investigate structural and physical properties of the 1/1 approximant of the icosahedral Al-Cu-Fe quasicrystal. Particular local structural arrangements of atoms, referred to here as clusters, have been analyzed with respect to their properties within the crystal structure. Artificial strain and cracks have been introduced to probe their mechanical properties, and artificial surfaces have been created to investigate their role for surface termination. From the energetics of the ab initio calculations results that flat surfaces cutting clusters are favored over puckered surfaces keeping clusters intact. The Vienna Ab-initio Simulation Package (VASP) was used for all calculations.

Circular dichroism in angle‐resolved photoemission spectroscopy of topological insulators

“…1 in Ref. [42])], is absent in the difference spectra. It is worth noting that such features persist even though the photon energy used in these studies varies from soft x-ray of the synchrotron radiation source [42,43,44,45] to the deep ultra-violet regime of laser source [46].…”

“…2 Mapping of topological spin-orbit texture with CD-ARPES 2.1 CD-ARPES from the surface states of TI ARPES provides the capability to directly identify the states which exhibits circular dichroic intensity. A few recent ARPES studies on topological insulators using circularly polarized photons observe strong CD from the surface states but very weak bulk contribution [42,43,44,45,46]. These studies focus on the prototypical materials Bi 2 Se 3 and Bi 2 Te 3 , where the surface states have a simple bandstructure composed of a single Dirac cone [2].…”

Topological Insulators

“…1 in Ref. [42])], is absent in the difference spectra. It is worth noting that such features persist even though the photon energy used in these studies varies from soft x-ray of the synchrotron radiation source [42,43,44,45] to the deep ultra-violet regime of laser source [46].…”

“…[42])], is absent in the difference spectra. It is worth noting that such features persist even though the photon energy used in these studies varies from soft x-ray of the synchrotron radiation source [42,43,44,45] to the deep ultra-violet regime of laser source [46]. This strongly suggests that the circularly dichroic ARPES spectra of topological insulators mainly originate from the initial states of the optical transition in the photoemission process.…”

“…A few recent ARPES studies on topological insulators using circularly polarized photons observe strong CD from the surface states but very weak bulk contribution [42,43,44,45,46]. These studies focus on the prototypical materials Bi 2 Se 3 and Bi 2 Te 3 , where the surface states have a simple bandstructure composed of a single Dirac cone [2].…”