Arrays of patch antennas have impacted modern telecommunications in the RF range significantly, owing to their versatility in tailoring the properties of the emitted radiation such as beam width and polarization, along with their ease of fabrication. At higher frequencies, in the terahertz (THz) range, there is a pressing need for a similar monolithic platform to realize and enable the advanced functionalities available in the RF technology. This platform would benefit a wide variety of fields such as astronomy, spectroscopy, wireless communications, and imaging. Here, we demonstrate THz lasers made of arrays of 10 × 10 patch antenna microcavities that provide up to 25 mW output power with robust single mode frequency and spatial mode. This device architecture leads to an unprecedented beam divergence, better than 2° × 2°, which depends only on the number of resonators. This allows to functionalize the device while preserving a high quality far-field pattern. By interconnecting the symmetric square microcavities with narrow plasmonic wires along one direction, we introduce an asymmetry into the originally degenerate and cross-polarized TM₀₁ and TM₁₀ modes, leading to a precise control of the resonant frequency detuning between the TM modes. This feature allows devices to be designed that radiate with any coherent polarization states from linear to circular. Large-scale full-wave simulations of the emission from entire arrays support our experimental results. Our platform provides a solution to finally achieve monolithic terahertz emitters with advanced integrated functionalities such as active beam steering and polarization control.

中文翻译：

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具有极低光束发散和偏振控制的单片贴片天线太赫兹激光器

贴片天线阵列在调整发射辐射的特性（如波束宽度和极化）的多功能性以及易于制造方面，已在RF范围内显着影响了现代电信。在太赫兹（THz）范围内的较高频率下，迫切需要一个类似的单片平台来实现并启用RF技术中可用的高级功能。该平台将使广泛的领域受益，例如天文学，光谱学，无线通信和成像。在这里，我们演示了由10×10贴片天线微腔阵列组成的THz激光器，该阵列可提供高达25 mW的输出功率以及强大的单模频率和空间模式。这种设备架构导致前所未有的光束发散度，优于2°×2°，这仅取决于谐振器的数量。这样可以在保持高质量远场图形的同时使设备功能化。通过将对称的方形微腔与狭窄的等离激元线沿着一个方向互连，我们将不对称性引入到最初退化和交叉极化的TM中₀₁和TM ₁₀模式，从而可以精确控制TM模式之间的谐振频率失谐。此功能使器件可以设计为以线性到圆形的任何相干偏振态辐射。整个阵列发射的大规模全波仿真支持了我们的实验结果。我们的平台提供了一种解决方案，可最终实现具有先进集成功能（如有源光束转向和偏振控制）的单片太赫兹发射器。