Dielectric waveguides have potential as transmission lines in subterahertz (sub-THz) applications due to their low-loss. A new application of a rectangular dielectric waveguide (RDW) for a THz superconducting receiver system for radio astronomy is investigated and demonstrated for the first time. The RDW can be used to transmit sub-THz local oscillator (LO) signals into the cryostat for driving the superconductor insulator superconductor mixer, with very low heat transfer. A series of RDWs with different lengths are fabricated. The measured average attenuation constants of the RDW are 0.034 and 0.069 dB/mm at 3.4 and 300 K measurement environments over 240–300 GHz, respectively. The double-sideband system noise temperature of the receiver system is also measured. With this LO signal feeding system, there is only 0.69 mW thermal transfer power from the 300 to the 3.4 K cold stage. Compared to traditional pumping signal feeding schemes, such as the horn-to-horn structure and beam splitter method, this approach outperforms the traditional schemes in terms of feeding flexibility, insertion loss, and thermal isolation for the cryostat. The proposed RDW can be widely applied to superconducting receivers for radio astronomy in the future.

中文翻译：

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用于超导接收器中亚太赫兹信号耦合的低损耗、绝热和柔性矩形介质波导

由于其低损耗，介电波导在亚太赫兹 (sub-THz) 应用中具有作为传输线的潜力。首次研究和演示了矩形介质波导 (RDW) 在射电天文太赫兹超导接收系统中的新应用。RDW 可用于将亚太赫兹本地振荡器 (LO) 信号传输到低温恒温器中，以驱动超导体绝缘体超导体混合器，热传递非常低。制造了一系列不同长度的 RDW。在 240–300 GHz 的 3.4 和 300 K 测量环境下，测得的 RDW 平均衰减常数分别为 0.034 和 0.069 dB/mm。还测量了接收器系统的双边带系统噪声温度。有了这个 LO 信号馈送系统，只有 0。从 300 到 3.4 K 冷级的 69 mW 热传递功率。与传统的泵浦信号馈送方案（例如喇叭到喇叭结构和分束器方法）相比，该方法在馈送灵活性、插入损耗和低温恒温器的热隔离方面优于传统方案。所提出的RDW未来可广泛应用于射电天文学的超导接收器。