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Updated: Jun 23, 2026

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Continuous voltage tunability of intersubband relaxation times in coupled SiGe quantum well structures using
P Rauter1, T Fromherz, N Q Vinh
1Institute of Semiconductor and Solid State Physics, University of Linz, Linz, Austria.
Abstract:
We demonstrate continuous voltage control of the nonradiative transition lifetime in semiconductor heterostructures. The results were obtained by picosecond time-resolved experiments on biased SiGe valence band quantum well structures using a free electron laser. By varying the applied voltage, the intersubband hole relaxation times for quantum well structures were varied by a factor of 2 as the wave functions and their overlaps were tuned. The range of magnitudes for the lifetime indicates a possible route to silicon-based quantum cascade lasers.
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