We report on the power loss mechanisms of hot electrons in as-grown and annealed n-type modulation-doped Al0.15Ga0.85As/GaAs1-xBix (x = 0 and 0.04) quantum well (QW) structures considering acoustic phonon interactions via the deformation potential (non-polar) and piezoelectric (polar) scatterings. The two-dimensional (2D) electron gas is heated by applying various electric fields under a steady-state magnetic field, and the effect of the applied electric field on the Shubnikov de Haas (SdH) oscillations is analyzed to investigate the power loss mechanism. The temperature of hot electrons (Te) has been obtained by comparing the lattice temperature and applied electric field dependencies of the SdH oscillation amplitude. The hot electron temperature is almost the same for both Bi-free and Bi-containing samples except for the sample annealed at higher than growth temperature (700°C). The electron temperature dependence of power loss is analyzed using current theoretical analytic models derived for 2D semiconductors. We find that energy relaxation occurs in the intermediate temperature regime, including mixing of piezoelectric and deformation potential scattering. The power loss of hot electrons is found to be proportional to (T_e^γ-T_L^γ) with  in the range from 2.4 to 4.2, which indicates that the hot electron relaxation is due to acoustic phonon scatterings via unscreened deformation potential and piezoelectric scattering. It is found that deformation potential scattering is dominant over piezoelectric scattering in the Bi-free sample, while the incorporation of Bi into the GaAs lattice makes these processes comparable. After thermal annealing at lower than growth temperature (350°C), the scattering mechanism switches from deformation potential to piezoelectric scattering. After thermal annealing at higher than growth temperature (700°C), the theoretical model does not fit to the experimental results due to degradation of the sample.

中文翻译：

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n 型调制掺杂的 AlGaAs/GaAsBi 量子阱异质结构中的功率损耗机制

我们报告了热电子在生长和退火的 n 型调制掺杂 Al0.15Ga0.85As/GaAs1-xBix (x = 0 和 0.04) 量子阱 (QW) 结构中的功率损耗机制，考虑到声子相互作用通过变形电位（非极性）和压电（极性）散射。通过在稳态磁场下施加各种电场来加热二维 (2D) 电子气，并分析施加的电场对 Shubnikov de Haas (SdH) 振荡的影响，以研究功率损耗机制。通过比较晶格温度和 SdH 振荡幅度的外加电场依赖性，获得了热电子 (Te) 的温度。除了在高于生长温度 (700°C) 下退火的样品外，不含 Bi 和含 Bi 样品的热电子温度几乎相同。使用为 2D 半导体导出的当前理论分析模型来分析功率损耗的电子温度依赖性。我们发现能量弛豫发生在中间温度范围内，包括压电和变形势散射的混合。发现热电子的功率损失与 (T_e^γ-T_L^γ) 成正比，其中  在 2.4 到 4.2 的范围内，这表明热电子弛豫是由于声子散射通过未屏蔽的变形电位和压电散射。发现在不含 Bi 的样品中，变形电位散射比压电散射占主导地位，而将 Bi 掺入 GaAs 晶格使这些过程具有可比性。在低于生长温度（350°C）的热退火后，散射机制从变形势转变为压电散射。在高于生长温度（700°C）的热退火后，由于样品降解，理论模型与实验结果不符。