Terahertz quantum cascade lasers based on interface roughness engineering in InGaAs/InAlAs heterostructures on InP

基于 InP 上 InGaAs/InAlAs 异质结构界面粗糙度工程的太赫兹量子级联激光器

• 批准号: 248490517
• 负责人: Professor Dr. William Ted Masselink
• 金额: --
• 依托单位: Institut für Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/248490517?language=en
• 关键词: Terahertz; quantum; cascade; lasers; based

The objective of this research is to demonstrate and investigate terahertz quantum cascade lasers based on a novel InGaAs-based active region. Indications are that lasers using this new design will operate near room-temperature; operation of THz QCLs at such high temperatures has not yet been demonstrated and would represent a revolutionary advance for terahertz instrumentation, opening new possibilities in terahertz research and applications.The proposed active region is the InGaAs/ InGaAs strain-compensated material system on InP. Both components of this material system are members of the well-established InGaAs alloy family on InP. By compensating the compressive strain of the InGaAs with In content less than 0.53 with the tensile strain of the InGaAs with In content greater than 0.53, strain-compensated structures with arbitrarily low conduction band offset can be realized using molecular beam epitaxy. The application of this system for THz QCLs has been described in a patent disclosure.The advantage of InGaAs/ InGaAs material system over GaAs/AlGaAs is the smaller electron effective mass in the quantum wells. Because of the higher laser gain associated with smaller electron effective mass, the proposed terahertz lasers are expected to have approximately 2.3 times higher gain and be able to operate at temperatures at least 100 K higher than is possible with the current state-of-the art GaAs/Al0.15Ga0.85As devices. Furthermore, the smaller effective mass in the proposed devices is expected to result in reduced interface roughness scattering and higher electron mobility that will further improve their performance.The advantage of the strain-compensated InGaAs material system over the lattice-matched InGaAs/InAlAs (or InGaAs/GaAsSb) material systems on InP for terahertz quantum cascade lasers is the possibility to choose the appropriate optimal conduction band offset in the range of 130 to 150 meV, in contrast to the high conduction band offset of 520 meV in the lattice matched InGaAs/InAlAs on InP or 360 meV in the lattice matched InGaAs/GaAsSb on InP.We expect that these improvements will allow us to create terahertz semiconductor lasers that can operate at near room temperature. We finally note that, unlike other approaches that are being suggested to improve the temperature performance of terahertz quantum cascade lasers, the proposed approach is a radical departure from established THz QCL approaches, but has the advantage that it relies on well-established growth techniques and material systems.

本研究的目的是展示和研究基于一种新颖的InGaAs基有源区的太赫兹量子级联激光器。有迹象表明，使用这种新设计的激光器将在室温附近工作; THz QCL在如此高的温度下工作尚未得到证实，这将代表太赫兹仪器的革命性进步，为太赫兹研究和应用开辟新的可能性。该材料系统的两种成分都是InP上成熟的InGaAs合金家族的成员。通过用In含量大于0.53的InGaAs的拉伸应变补偿In含量小于0.53的InGaAs的压缩应变，可以使用分子束外延实现具有任意低导带偏移的应变补偿结构。InGaAs/ InGaAs材料系统相对于GaAs/AlGaAs材料系统的优点是量子威尔斯阱中的电子有效质量较小。由于更高的激光增益与更小的电子有效质量相关联，预期所提出的太赫兹激光器具有大约2.3倍的增益，并且能够在比当前最先进的GaAs/Al0.15Ga0.85As器件可能的温度高至少100 K的温度下工作。此外，委员会认为，在所提出的器件中，较小的有效质量预期会导致减小的界面粗糙散射和更高的电子迁移率，这将进一步改善它们的性能。（或InGaAs/GaAsSb）的InP材料系统的太赫兹量子级联激光器是可能选择适当的最佳导带偏移的范围内，130至150 meV，与InP上晶格匹配的InGaAs/InAlAs中520 meV或InP上晶格匹配的InGaAs/GaAsSb中360 meV的高导带偏移形成对比。我们期望这些改进将使我们能够创建可以在接近室温下工作的太赫兹半导体激光器。最后，我们注意到，与其他建议提高太赫兹量子级联激光器的温度性能的方法不同，所提出的方法与现有的太赫兹QCL方法完全不同，但其优势在于它依赖于成熟的生长技术和材料系统。