Electrically Pumped Terahertz Frequency Comb Based on Actively Mode-locked Resonant Tunneling Diode

TL;DR

This paper presents a novel, electrically pumped, room-temperature terahertz frequency comb using an actively mode-locked resonant tunneling diode, enabling broadband, tunable, and high-speed wireless communication applications.

Contribution

It introduces a compact, broadband, tunable THz frequency comb source based on an actively mode-locked resonant tunneling diode integrated in a metallic waveguide, operable at room temperature.

Findings

Broadband comb spectrum from 0.14 to 0.325 THz at room temperature.

Repetition frequency tunable from 0.9 to 50 GHz.

Achieved 120 Gbps data rate in wireless communications.

Abstract

Terahertz (THz) frequency combs (TFCs) are promising for numerous applications in spectroscopy, metrology, sensing, and wireless communications. However, the practical applications of TFCs have been hindered thus far by the need for cryogenic cooling, limited bandwidth, and bulky configuration, largely due to the lack of advanced THz sources. Here, we report an electrically pumped, room-temperature, broadband, compact, and tunable TFC by integrating an actively mode-locked resonant tunneling diode (RTD) in a metallic waveguide. By injecting a strong, continuous-wave radio frequency (RF) signal into a direct-current-driven RTD oscillator, we experimentally demonstrate a broadband, offset-free comb spectrum spanning more than one octave, from 0.14 to 0.325 THz at room temperature. Moreover, we show that the repetition frequency of the TFC can be tuned from 0.9 to 50 GHz by the injected RF signal, and a 120 Gbps (16 Gbps per channel) data rate can be achieved in the TFC-based high-speed single-channel (multi-channel) wireless communications.