A terahertz variable attenuator integrated on a nonradiative guide controlled by externally induced photoconductivity is proposed. Our device is constructed using high-resistivity silicon as a dielectric channel of the waveguide sandwiched between parallel conducting plates. By irradiating an excitation light to the side surface of the channel, photoinduced carriers are generated involving attenuation for terahertz waves propagating through the channel. We experimentally demonstrate attenuation of 0.50 dB/cm/mW at 300 GHz. The use of the nonradiative guide simplifies the light irradiation scheme and contributes to integrate other functions such as bending, filtering, splitting, and combining without radiation losses. We also discuss its unique frequency dependence, in which the attenuation increases as the frequency decreases.

中文翻译：

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可变太赫兹衰减器集成在使用光致载波的非辐射波导上

提出了一种集成在由外部感应光电导控制的非辐射波导上的太赫兹可变衰减器。我们的设备使用高电阻率硅作为夹在平行导电板之间的波导的介电通道构成。通过将激发光照射到通道的侧表面，产生光致载流子，包括对通过通道传播的太赫兹波的衰减。我们通过实验证明在 300 GHz 时衰减为 0.50 dB/cm/mW。非辐射波导的使用简化了光照射方案，并有助于在没有辐射损失​​的情况下集成其他功能，例如弯曲、过滤、分裂和组合。我们还讨论了它独特的频率依赖性，其中衰减随着频率的降低而增加。