Opt Lett. 2019 Jan 1;44(1):98-101. doi: 10.1364/OL.44.000098.
We study selective upconversion of optical signals according to their detailed transverse electromagnetic modes and demonstrate its proof of operation in a nonlinear crystal. The mode selectivity is achieved by preparing the pump wave in an optimized spatial profile to drive the upconversion. For signals in the Laguerre-Gaussian modes, we show that a mode can be converted with up to 60 times higher efficiency than an overlapping, but orthogonal, mode. This nonlinear optical approach may find applications in compressive imaging, pattern recognition, quantum communications, and others, where the existing linear optical methods are limited.
我们根据光信号的详细横电磁模式研究了光信号的选择上转换，并在非线性晶体中验证了其工作原理。通过优化泵浦波的空间分布来驱动上转换，实现了模式的选择性。对于拉盖尔-高斯模式的信号，我们表明可以将一个模式的转换效率提高至与重叠但正交模式相比高达 60 倍。这种非线性光学方法可能在压缩成像、模式识别、量子通信等领域有应用，在这些领域中现有的线性光学方法受到限制。
