Silicon-based long-wavelength III–V quantum-dot lasers

The realization of electrically-pumped lasers on a Si platform will permit the creation of complex optoelectronic circuits, which will enable chip-to-chip and system-to-system optical communication. Direct epitaxial growth of III-V semiconductor materials on Si or Ge substrates is the most promising approach for producing lasers on Si. III-V compound quantum dots - semiconductor nanosized crystals - are very attractive for producing III-V/Si laser diodes with the advantages of lower threshold current density and less sensitivity to defects relative to conventional quantum wells. Here we present studies on the development of InAs/GaAs quantum-dot lasers monolithically grown on Si, Ge, and Ge-on-Si substrates. Room-temperature lasing near the telecommunications wavelength of 1300 nm have been demonstrated at room temperature with low threshold current densities for InAs/GaAs quantum-dot lasers grown on both Si, and Ge substrates.