Universal symmetry-protected persistent spin textures in noncentrosymmetric crystals

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Mechanics

Background:

• Crystal symmetry governs fundamental material properties like electron transport and magnetism.
• Persistent spin texture (PST) offers extended spin lifetime and efficient spin accumulation by maintaining spin polarization independent of momentum.
• Understanding PST is crucial for advancing spintronic technologies.

Purpose of the Study:

• To establish the general conditions for symmetry-protected PST in bulk crystals.
• To systematically analyze crystallographic space groups for the presence of PST.
• To identify regions in the Brillouin zone hosting PST and their spin polarization directions.

Main Methods:

• Systematic analysis of all noncentrosymmetric crystallographic space groups.
• Application of group theory to identify PST hosting regions and spin polarization directions.
• First-principles calculations for validation in representative materials.

Main Results:

• PST is universally present in all nonmagnetic solids lacking inversion symmetry, excluding the trivial space group P1.
• Group theory precisely identifies Brillouin zone regions and spin polarization directions for PST.
• Findings are supported by first-principles calculations on specific materials.

Conclusions:

• The study establishes universal conditions for symmetry-protected PST in bulk crystals.
• This work provides a pathway for discovering new robust spintronic materials based on PST.
• The findings highlight the fundamental role of crystal symmetry in electronic and spin properties.