Enhanced T0values in GaSb/AlSb multiquantum well heterostructures

The material system GaSb/AlSb is discussed with respect to laser applications. Optical gain measurements reveal that in GaSb/AlSb multiquantum well heterostructures, energy-dependent resonant loss mechanisms such as intervalence band absorption and Auger recombination are significantly reduced as compared to bulk GaSb where these losses are resonant. The switch-off of the resonant loss processes is mirrored by the large ratio of the T0values between the two-dimensional and the three-dimensional carrier system. Non-parabolicity effects present in the multiquantum well band structure are proposed to explain the switch-off of the loss resonance in GaSb/AlSb multiquantum well heterostructures.