Observation of Fermi-Arc Spin Texture in TaAs

Area of Science:

• Condensed Matter Physics
• Materials Science
• Topological Materials

Background:

• Weyl semimetals are a novel class of topological materials exhibiting unique electronic properties.
• TaAs is a recently discovered Weyl semimetal with potential applications in next-generation electronics.
• Understanding the spin texture of surface states is crucial for characterizing topological properties.

Purpose of the Study:

• To experimentally investigate the spin texture of surface Fermi arcs in TaAs.
• To verify the topological nature of the Weyl semimetal state in TaAs.
• To compare experimental findings with theoretical predictions.

Main Methods:

• Utilizing spin- and angle-resolved photoemission spectroscopy (SARPES).
• Performing first-principles calculations to model electronic structure and spin properties.
• Analyzing experimental data for spin polarization and symmetry properties.

Main Results:

• Experimental evidence confirms that the surface Fermi arcs in TaAs are spin-polarized.
• The observed spin texture aligns with mirror and time-reversal symmetries.
• First-principles calculations accurately reproduce the experimental spin texture.

Conclusions:

• The spin-polarized Fermi arcs provide strong evidence for the topologically nontrivial Weyl semimetal state in TaAs.
• Experimental and theoretical consistency validates the predicted chirality distribution of Weyl nodes.
• This study solidifies TaAs as a key material for exploring Weyl semimetal physics.