Controlling the helicity of light by electrical magnetization switching

Area of Science:

• Optoelectronics
• Spintronics
• Materials Science

Background:

• Information transfer and processing rely on controlling light intensity and charge current.
• Information storage utilizes electron spin and ferromagnetism.
• A gap exists in modulating light's circular polarization using electrical magnetization control.

Purpose of the Study:

• To establish a link between photonics, electronics, and spintronics by electrically controlling light's circular polarization.
• To demonstrate a method for modulating light polarization via magnetization at room temperature and zero magnetic field.

Main Methods:

• Utilizing spin-orbit torque to generate spin currents from charge currents, enabling electrical switching of magnetization.
• Injecting spin-polarized carriers into semiconductors.
• Leveraging electron spin-to-photon angular momentum transfer to control emitted light's circular polarization.

Main Results:

• Demonstrated electrical control of light's circular polarization at room temperature and zero magnetic field.
• Achieved nonvolatile control of magnetization through spin-photon conversion.
• Established a method for integrating information transfer, processing, and storage.

Conclusions:

• The findings bridge photonics, electronics, and spintronics, enabling new applications in information technology.
• Opens pathways for ultrafast modulation of circular polarization and spin injection.
• Potential for transformative applications in quantum information processing and advanced spectroscopies.