THz-to-Optical Conversion in Wireless Communications Using an Ultra-Broadband Plasmonic Modulator

TL;DR

This paper demonstrates a seamless integration of THz wireless links with fiber-optic networks using a novel ultra-broadband silicon-plasmonic modulator for direct terahertz-to-optical conversion at 50 Gbit/s.

Contribution

It introduces the first THz-to-optical conversion device capable of integrating wireless THz links into fiber-optic systems with high bandwidth.

Findings

Achieved 50 Gbit/s data transmission over a 0.2885 THz carrier.

Used an ultra-broadband silicon-plasmonic modulator with >0.36 THz bandwidth.

Successfully demonstrated direct THz-to-optical conversion in a wireless link.

Abstract

Future wireless communication networks have to handle data rates of tens or even hundreds of Gbit/s per link, requiring carrier frequencies in the unallocated terahertz (THz) spectrum. In this context, seamless integration of THz links into existing fiber-optic infrastructures is of great importance to complement the inherent portability and flexibility advantages of wireless networks by the reliable and virtually unlimited capacity of optical transmission systems. On the technological level, this requires novel device and signal processing concepts for direct conversion of data streams between the THz and the optical domains. Here, we report on the first demonstration of a THz link that is seamlessly integrated into a fiber-optic network using direct terahertz-to-optical (T/O) conversion at the wireless receiver. We exploit an ultra-broadband silicon-plasmonic modulator having a 3 dB bandwidth in excess of 0.36 THz for T/O conversion of a 50 Gbit/s data stream that is transmitted on a 0.2885 THz carrier over a 16 m-long wireless link. Optical-to-terahertz (O/T) conversion at the wireless transmitter relies on photomixing in a uni-travelling-carrier photodiode.