Overlap structure of Fano-resonance profiles of excitons in a semiconductor quantum well
Overlap structure of Fano-resonance profiles of excitons in a semiconductor quantum well
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半导体量子阱中激子法诺共振剖面的重叠结构
DOI：
10.1103/physrevb.64.075318
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发表时间：
2001
影响因子：
3.7
通讯作者：
K. Hino
中科院分区：
文献类型：
--
作者：
K. Hino
基于激子的4×4 Luttinger哈密顿量，研究了属于Γ7+-不可约表象的G a A S/A L 0 3Ga0 7As量子阱中激子的Fano共振.利用绝热展开和R矩阵传播方法解决了共振态的多通道散射问题，使我们能够在不引入任何经验展宽参数的情况下实现高分辨率计算。计算了100-50−？厚量子阱中激子的吸收光谱，给出了激子光学活性态和非活性激子态的详细法诺共振谱。具体地说，我们注意到不同子带的Fano共振之间的复杂干涉发生在一个超过350？的量子井中。所得到的复合剖面本身表现为重叠共振，与相应的孤立剖面相比，伴随着峰高、峰宽和不对称图案的显著变化。采用Fano模型对一条明渠和两条闭渠进行了定性评价。此外，还利用本征位相和给出的时间延迟进行了定量解释。
The Fano resonance of an exciton in a quantum well of G a A s/A l 0.3 Ga 0.7 As belonging to the Γ 7+-irreducible representation is investigated based on the excitonic 4× 4 Luttinger Hamiltonian. Multichannel scattering problems for the resonance states are solved by virtue of the adiabatic expansion and the R-matrix propagation method, which enable us to implement high-resolution calculations without introducing any empirical broadening parameters. Absorption spectra for excitons are calculated in 100–5 0 0− Å-thick quantum wells, and detailed Fano-resonance profiles for both optically active and inactive exciton states are revealed. Specifically, it is noticed that complicated interference between Fano resonances pertaining to different subbands occurs in a quantum well of more than 350 Å. A resulting composite profile manifests itself as overlap resonance, accompanying marked changes in a peak height, a width, and an asymmetry pattern from the corresponding isolated profiles. Such changes are evaluated qualitatively by use of Fano’s model for one open-channel and two closed-channels. Moreover, quantitative interpretations are also made by employing a time delay given by an eigenphase sum.