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Updated: Jun 23, 2026

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier
Published on: July 12, 2017
Hot electrons and curves of constant gain in long wavelength quantum well lasers
Abstract:
In long wavelength quantum well lasers the effective electron temperature (T(e)) is often a strong function of the pump current and hence the T(e) correlates with the carrier concentration n in the active region. On the other hand, the material gain g in the active layer depends on both variables, g=g(n,T(e) ). We discuss a convenient way of analyzing this situation, based on considering the contours of constant gain g on the surface g(n,T(e) ). This is qualitatively illustrated with two model examples involving quantum well lasers, the long-wavelength quantum well laser with current dominated by the Auger recombination and the unipolar quantum cascade laser.
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