Integrated Broadband Graphene Modulator

Synopsis

Integrated optical modulators, crucial in communication, imaging, sensing, and defence, especially excel in the mid-infrared (mid-IR) and terahertz (THz) spectrum. This graphene modulator offer unparalleled performance across these frequencies, featuring a concentric circular grating that allows for exceptional broadband absorption, offering high modulation depth and faster speeds.

Opportunity

High-performance, integrated optical modulators that excel in the mid-IR and THz frequencies are vital for advanced applications such as free space communication, LIDAR, imaging as well as various sensing and spectroscopy techniques. However, current technologies are unable to provide a solution that achieves high modulation depth and high-speed modulation across these critical wavelength regimes.

Technology

This technology leverages an integrated graphene modulator for efficient optical signal modulation over a broad spectrum:

Wavelength coverage suitable for mid-IR and THz frequencies, along with potential applications in UV, visible and near-IR spectrums.
Construction includes a graphene layer situated above a specialised laser electrode.
The laser electrode comprises a concentric circular metal grating, optimising the interaction between graphene and the laser field.

Figure 1: Cross-section of graphene-based broadband optical modulator.

Applications & Advantages

This graphene-based broadband optical modulator is suitable for numerous applications, from telecommunication to advanced sensing technologies, providing:

Broadband absorption capabilities across mid-IR frequencies, significantly enhancing system performance by reducing data transfer delays.
A high modulation depth due to strong graphene interactions within the laser cavity, combined with rapid modulation speeds enabled by the device’s compact design.