Charge-separation effects in 1.3 mu m GaAsSb type-II quantum-well laser gain

A microscopic laser theory is used to investigate gain and threshold proper ties in a GaAsSb quantum-well laser. Depending on the geometry of the type- II quantum-well gain region, there may be appreciable band distortions due to electron-hole charge separation. The charge separation and accompanying band distortions lead to interesting optical behaviors, such as excitation- dependent oscillator strength and band edge energies. Implications to laser operation include significant blueshift of the gain peak with increasing i njection current, and inhibition of spontaneous emission, which may result in threshold current reduction. (C) 2001 American Institute of Physics.