We propose and experimentally demonstrate on-chip optical encoder and decoder with ultra-low power consumption. The key device is a silicon photonic crystal (PC) L3 nanocavity with small mode volume. Consequently, the nonlinear effects in the nanocavity are strongly enhanced and could be excited by lower powers. Leveraging different optical power levels, the transmission spectra of the PC nanocavity could be flexibly manipulated. By utilizing proper determining powers, the output powers could be defined as the corresponding optical codes. In the experiment, the binary encoder and decoder are successfully demonstrated with required optical powers of 0.04 mW and 0.032 mW, respectively. Unlike most previous optical encoders and decoders with high powers (tens of milliwatts) or large size (several square millimeters), our scheme which could simultaneously realize the optical encoder and decoder only requires ultra-low powers as 0.04 mW with a compact size of $100~\mu \text{m}^{2}$ . To the best of our knowledge, it is a record combined the power consumption and device size for on-chip optical encoder and decoder.

中文翻译：

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超低功耗的光学二进制编解码器

我们提出并实验证明了具有超低功耗的片上光学编码器和解码器。关键器件是具有小模体积的硅光子晶体 (PC) L3 纳米腔。因此，纳米腔中的非线性效应被强烈增强并且可以被较低的功率激发。利用不同的光功率水平，可以灵活地操纵 PC 纳米腔的透射光谱。通过使用适当的确定功率，可以将输出功率定义为相应的光代码。在实验中，二进制编码器和解码器成功地演示了所需的光功率分别为 0.04 mW 和 0.032 mW。不同于以往大多数大功率（几十毫瓦）或大尺寸（几平方毫米）的光学编码器和解码器，我们可以同时实现光学编码器和解码器的方案只需要 0.04 mW 的超低功率，尺寸紧凑，为 $100~\mu \text{m}^{2}$ 。据我们所知，这是结合片上光学编码器和解码器的功耗和器件尺寸的记录。