We report the first implementation of an advanced waveguide structure, consisting of GaSb separate confinement layers, n-doped InAs/AlSb superlattice intermediate cladding layers, and n + -doped InAs0.91Sb0.09 plasmon-enhanced cladding layers for GaSb-based interband cascade lasers (ICLs) with lasing wavelengths in the 3 to 4 μm wavelength region. This advanced waveguide configuration for ICLs can have improved thermal dissipation and enhanced optical confinement. Although the grown ICL wafers had significant layer thickness deviations from the designed values, devices made from them exhibited room temperature (RT) threshold current densities as low as 148 A / cm2 and high voltage efficiencies (e.g., 69%), implying a considerable potential of the advanced waveguide configuration for further improved device performance. A comparative study among the devices revealed how the structural variations could affect the carrier transport and threshold voltage, providing useful guidance for future research. Additionally, the ICLs tested here had characteristic temperatures of nearly 60 K, which are the highest among RT ICLs with similar lasing wavelengths, supporting the further development of the advanced waveguide in GaSb-based ICLs operating in this wavelength range.

中文翻译：

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具有先进波导的带间级联激光器，工作波长范围为 3 至 4 μm

我们报告了先进波导结构的首次实现，该结构由 GaSb 单独限制层、n 掺杂 InAs/AlSb 超晶格中间包层和 n + 掺杂 InAs0.91Sb0.09 等离子体增强包层组成，用于基于 GaSb 的带间级联激光波长在 3 至 4 μm 波长范围内的激光器 (ICL)。这种 ICL 的先进波导配置可以改善散热并增强光学限制。尽管生长的 ICL 晶圆与设计值存在显着的层厚度偏差，但由其制成的器件表现出低至 148 A/cm2 的室温 (RT) 阈值电流密度和高电压效率（例如 69%），这意味着相当大的潜力先进的波导配置进一步提高了器件性能。这些器件之间的比较研究揭示了结构变化如何影响载流子传输和阈值电压，为未来的研究提供有用的指导。此外，这里测试的 ICL 具有接近 60 K 的特征温度，这是具有类似激光波长的 RT ICL 中最高的，支持在该波长范围内工作的基于 GaSb 的 ICL 中先进波导的进一步开发。