Room temperature magneto-optic effect in silicon light-emitting diodes.

Area of Science:

• Solid State Physics
• Materials Science
• Optoelectronics

Background:

• Spin-selective recombination in weakly spin-orbit coupled materials can yield large magnetic-field effects.
• Observing spin-dependent recombination in silicon via magneto-electroluminescence is challenging due to its indirect band-gap and difficulty separating effects.

Purpose of the Study:

• To overcome challenges in observing spin-dependent recombination in silicon.
• To measure magneto-electroluminescence in silicon light-emitting diodes (LEDs).

Main Methods:

• Fabrication of silicon LEDs using gas immersion laser doping for efficient emission and defined geometry.
• Measurement of electroluminescence under a seven Tesla magnetic field near room temperature.

Main Results:

• Achieved efficient electroluminescence in silicon LEDs.
• Suppressed classical magnetoresistance effects to a few percent.
• Observed up to 300% enhancement in electroluminescence near room temperature in a magnetic field.

Conclusions:

• Demonstrated successful measurement of magneto-electroluminescence in silicon.
• Confirmed that controlling the spin degree of freedom strongly impacts silicon LED efficiency.
• Opened new avenues for spin-based electronics and optoelectronics in silicon.