Active Terahertz two-wire waveguides (market study).

目前的提案涉及一项市场研究，该研究涉及开发一种有源双线波导，通过直接在引导结构内产生太赫兹电场，在太赫兹（THz）频率范围内工作。在1 THz以上的频率下，具有低色散和低损耗的波导的开发对于实现宽带亚皮秒THz脉冲的无失真传播以及实现未来THz通信网络、THz时间光谱和传感的互连至关重要。因此，选择合适的材料和合适的几何形状来实现太赫兹波导成为一个根本性的挑战。此外，取决于几何形状，由于波导模式和自由传播入射模式之间的大失配，宽带传播THz波到波导的有效耦合可能是一个问题。迄今为止，已经报道了几种基于电介质和金属结构的太赫兹波导。一方面，已经开发了基于介质的波导，例如蓝宝石光纤、塑料带波导和亚波长光纤。另一方面，诸如单线波导、平行板波导（PPWG）和双线波导的金属波导由于其支持（几乎）非色散横向电磁模式（TEM）的能力而可以传播具有低色散的单周期THz脉冲。在这些配置中，双线波导似乎是最有前途的一个，尽管事实上，耦合效率的问题仍然需要解决。然而，由两个金属线之间的砷化镓件（起到THz发射器的作用）的实施例制成的有源双线波导导致直接在引导结构内产生THz电场。通过比较的耦合效率的有源配置与标准的情况下，在波导外产生的辐射，我们报告了一个恒定的照明功率和施加的电位高出63倍的能量吞吐量。因此，这种进步肯定会为进一步开发紧凑型THz系统开辟新的机会。

The current proposal deals with a market study related to the development of an active two-wire waveguide, operating in the Terahertz (THz) frequency range, by generating a THz electric field directly within the guiding structure. The development of waveguides with low dispersion as well as low losses at frequencies above 1 THz is essential to enable undistorted propagation of broadband sub-picosecond THz pulses and to realize interconnects for future THz communication networks, THz-time spectroscopy and sensing. Choosing the appropriate material and the suitable geometry for the realization of THz waveguides is thus becoming a fundamental challenge. Furthermore, depending on the geometry, efficient coupling of broadband propagating THz waves to the waveguide can be an issue due to a large mismatch between the waveguide mode and the free propagating incident mode. To date, several THz waveguides based on dielectric and metallic structures have been reported. On the one hand, dielectric based waveguides such as sapphire fibers, plastic ribbon waveguides and sub-wavelength fibers have been developed. On the other hand, metallic waveguides such as single wire waveguides, parallel plate waveguides (PPWG) and two wire waveguides can propagate single cycle THz pulses with low dispersion due to their ability to support an (almost) non-dispersive transverse electromagnetic mode (TEM). Among these configurations, the two-wire waveguide appears to be the most promising one, despite the fact that coupling efficiency issues still have to be addressed. However, an active two-wire waveguide made by the embodiment of a gallium arsenide piece (playing the role of the THz emitter) between the two metallic wires, results in the generation of a THz electric field directly within the guiding structure. By comparing the coupling efficiency of the active configuration with that of the standard case in which the radiation is generated outside the waveguide, we reported a 63 times higher energy throughput for a constant illumination power and applied potential. Such an advancement will thus certainly open new opportunities in further development of compact THz systems.