Current-induced Orbital and Spin Magnetizations in Crystals with Helical Structure

Area of Science:

• Condensed Matter Physics
• Solid State Physics
• Materials Science

Background:

• Helical lattice structures in crystals can exhibit unique electronic and magnetic properties.
• Understanding current-induced phenomena is crucial for developing novel electronic devices.

Purpose of the Study:

• To theoretically demonstrate the induction of orbital and spin magnetizations along a helical axis by an electric current.
• To investigate the origin of the current-induced spin magnetization and its dependence on helix handedness.

Main Methods:

• Development of a simplified tight-binding model for theoretical calculations.
• Analysis of the electronic band structure and Fermi surface properties of helical crystals.

Main Results:

• Electric current along the helical axis induces both orbital and spin magnetizations parallel to this axis.
• The induced magnetizations are found to be opposite for right-handed and left-handed helical structures.
• The spin magnetization arises from a radial spin texture present on the Fermi surface.

Conclusions:

• Helical crystals offer a unique platform for generating axial spin and orbital magnetizations via electrical currents.
• The observed phenomenon contrasts with Rashba systems, highlighting distinct spin dynamics in helical materials.
• These findings pave the way for potential applications in spintronics and novel magnetic devices.