Integrated terahertz frequency generator

太赫兹辐射在100 GHz到30太赫兹的范围内，已被用于天文学和分析科学的研究。光子学和纳米技术的最新进展现在使新的太赫兹发电技术的创新研究成为可能。太赫兹辐射的一种技术是通过两束约0.8微米的光入射到低温生长的GaAs光混合器上的外差光电混合。另一种技术是利用量子级联激光器获得频率不可调谐、工作在低温下的太赫兹辐射，随着太赫兹频率的降低，对级联激光器的要求越来越高。第三种技术是在低输出平均功率的光学工作台内使用飞秒激光器。1.55微米的光子技术已经在信息和电信领域得到了很好的确立和探索。我们将研究和开发一种集成的太赫兹频率发生器，通过外差光合成约1.55微米的两束光，获得从100 GHz到6 THz的太赫兹辐射。该发生器由1.55微米左右的双模可调谐量子点锁相半导体激光器、高功率量子点半导体放大器、超快光电探测器(低温生长的InGaAs)和太赫兹天线组成。这种太赫兹发生器性价比高，坚固耐用，非常紧凑，而且集成在一起。太赫兹发生器既可用于传感，也可用于通信。这些应用包括：(1)生物、医疗和制药科学，包括生物分子、药物、癌症组织、DNA、药物、蛋白质和细菌的检测；(2)半导体和其他工业应用，包括材料评估、硅太阳能电池、纳米复合材料、聚合物薄膜和介电薄膜的检测和故障分析；(3)安全筛选，包括识别每种爆炸物和麻醉剂的特征；(4)信息和通信技术，包括未来可能达到10 Gb/S的室内和室外高速无线通信；(5)地球和空间科学，包括污染分析和观测，以及气体传感；以及(6)基础科学，包括食品质量控制。

Terahertz radiation, in the range of 100 GHz to 30 THz, has been investigated for astronomy and analytical science. Recent advancements in photonics and nanotechnology are now enabling innovative research of new THz generation technologies. One technique for terahertz radiation is to use heterodyne photomixing by two lights of around ~0.8-micron incident on a low temperature grown GaAs photomixer. Another technique is to use quantum cascade lasers to obtain THz radiation with no frequency tunability and working at low temperature, and more cascade lasers are required with the decrease of THz. The third technique is to use a femto second laser within an optical bench with low output average power. Photonic technologies at 1.55 micron have been well established and explored for information and telecommunication sector. We will investigate and develop an integrated terahertz frequency generator by heterodyne photomixing of two lights at around 1.55-micron to obtain THz radiation from 100 GHz to 6 THz. The generator is composed of a dual-mode and tunable quantum-dot phase-locked semiconductor laser at around 1.55 micron, a high-power quantum-dot semiconductor amplifier, an ultrafast photomixer (low-temperature grown InGaAs) and a THz antenna. This THz generator will be cost-effective, robust, very compact, and integrated. The THz generator can be used for both sensing and communications. The applications include (1) detection of biological, medical and pharmaceutical science including biomolecules, medicines, cancer tissue, DNA, drug, proteins and bacteria, (2) semiconductor and other industrial applications including material evaluations, inspection of silicon solar cells, nanocomposites, polyfilms and dielectric films and fault analysis, (3) security screening including identifying signature of every explosive and narcotic, (4) information and communication technology including indoor and outdoor high speed wireless communications with possible 10 Gb/s in the future, (5) earth and space science including pollution analysis and observation, and gas sensing, and (6) basic science including food quality control.