The University of California Berkeley engineers have devised a new technique to develop nanolasers on a silicon surface directly.
The electronics engineers have been trying to integrate silicon with optoelectronics for years. However, silicon is incompatible with the III-V materials needed for optoelectronics.
The scientists used indium gallium arsenide, an III-V material, to grow nano-scale pillars onto a silicon surface at cool temperature of 400°C. The nano size of the pillars enabled the engineers to develop the III-V materials at a low temperature without affecting the function of the silicon electronics.
The engineers showed that the nano-scale pillars can produce near infrared laser light at nearly 950 nm wavelength at room temperature. The nano-scale pillars' hexagonal shape crystal structure produces an effective light-trapping optical cavity. In the optical cavity, light travels up and down the structure in a helical manner and magnifies through this optical feedback mechanism.