Ultrafast charge and field driven optical modulators and switches

Abstract

Electro-optic modulators are critical building blocks for many signal processing systems which adhere to requirements given by both electrical and optical constraints. We discuss the fundamental speed limitations of recently developed charge and field driven nanophotonic electro-optic devices enabling the next generation of electro-optic modulators featuring a significantly improved device performance regarding modulation efficiency (V π L < 1 Vcm), device footprint (< 1 mm 2 ) and bandwidth (> 100 GHz). We show that the practical limits of the operation speed is for both, ferroelectric Pockels modulators and the porpoised transparent conducting oxides (ITO) modulators, determined by the frequency response of the corresponding electronic circuit driving the modulator.

Demultiplexing OAM beams via Fourier optical convolutional neural network

“…[108][109][110] Furthermore, these topologically safeguarded modes can be utilized in long-distance free-space communication links, capitalizing on the non-diffracting and self-healing properties of OAM. [111][112][113][114][115][116] In this previous work, we proposed a swift multiplexing and demultiplexing scheme, supplemented by an 'intelligent' active demultiplexing mechanism that facilitates adaptivity to the transmission medium. The overarching goal is to achieve GHz-speed optical communication suitable for underwater deployment.…”