Identification of the mode, polarization, wavelength and intensity of light using a one-pixel device on an optical fibre tip

Abstract

The in situ monitoring of different parameters of light is important for the development of high-capacity information technology. However, the number of light states increases exponentially as parameters are added, and conventional detection systems must split light signals into numerous channels and photodetectors using bulky optics. Here we report a one-pixel device that is integrated on an optical fibre tip and can simultaneously resolve the mode, polarization, wavelength and intensity of light. The device, which can generate spatially dependent responses, is based on twisted, dichroic layers of two-dimensional black phosphorus and black arsenic–phosphorus, as well as ring-grating-like electrodes. The device generates six distinct photoresponses and we use it to achieve four-dimensional light detection with one-shot measurements, creating a large recognizable input-state space of around 104. We also show that the approach can be used for multidimensional image encryption communication. A one-pixel device that is made of layers of twisted dichroic materials and ring-grating-like electrodes—and is integrated on the tip of an optical fibre—can be used to simultaneously resolve the mode, polarization, wavelength and intensity of input light in one-shot measurements.