Electronic Recombination/Generation Mechanisms (1.6, 1.7)

1.6. List and explain all the basic electronic recombination/generation mechanisms. Which one is required for lasers to operate?

  • Spontaneous Recombination
  • Stimulated Emission
  • Photon Absorption
  • Non-radiative Recombination

1.7 Describe the main ways of non-radiative recombination in semiconductor lasers/

Non-radiative recombination:

  • A conduction band electron and a valence band hole recombine without generating photons
  • Energy dissipated by heat or kinetic energy
  1. Non-radiative recombination by crystal defects, surfaces:
  • Electron and hold recombine but do not generate photon
  • Proportional to carrier density N
  • Caused by surface, point defect, interface, etc

2. Auger Recombination:

  • Energy from recombination is transferred to another electron or hole instead of photon generation
  • Proportional to carrier density N^3.
  • Energy from electron and hole is transferred to a third particle.