Semiconductor Photonics Devices

About

Our Semiconductor Photonic Devices group brings together expertise in design, fabrication, and characterisation to develop innovative semiconductor-based photonic technologies for a range of cutting-edge applications.

By combining deep knowledge of photonic device physics with advanced simulation tools and strong integration with the UK and global supply chains, we develop novel approaches to realise high-performance photonic devices tailored to emerging needs in communications, sensing, and quantum technologies.

We apply rigorous design processes and feedback-driven optimisation to push the boundaries of what's possible in semiconductor photonics.

Our research includes:

Development of advanced lasers such as PCSELs, DFBs, quantum dot, and high-power edge emitters
Novel photodetectors including InGaAs/InP APDs for high-speed and sensitive applications
THz and mid-IR sources using resonant tunnelling diodes, quantum-cascade lasers, and non-linear optics
Integration of III-V materials and epitaxial techniques for custom photonic solutions
Cutting-edge micro-LEDs and VCSELs for optical systems and photonic integrated circuits
Device characterisation and simulation for continuous performance optimisation

Our Projects

Integrated Solid-State Laser Beam Steering with PCSEL Arrays and Photonic Lanterns (I-STEER)

Conventional laser steering technologies are often costly, bulky, and fragile. One or more of these disadvantages makes them sub-optimal for many important applications, including laser imaging systems for automotive applications, space-based laser communications systems, and drone-based remote sensing systems. In this project, we exploit recent advances in two key integrated optical technologies - coherent Photonic Crystal Surface Emitting Laser (PCSEL) diode arrays and three-dimensional optical waveguide devices known as "integrated photonic lanterns" - to develop fully Integrated Solid-State Steerable Lasers (I-STEER) that can deliver agile beam steering in two dimensions and can, in principle, function at any diode laser wavelength.

Through the I-STEER project, we aim to redefine the laser diode as an all-electronic integrated steerable light source enabling new functionally in countless applications including free-space optical communications and LiDAR.

R1 R. J. E. Taylor, et al., Sci. Rep. 5, 13203 (2015) doi.org/10.1038/srep13203,

R2 D. Choudhury, et al., Nat. Commun. 11, 5217 (2020) doi.org/10.1038/s41467-020-18818-6

Avalanche Photodiodes for High-Precision Optical Time-Domain Reflectometry (VOLTAIRE)

VOLTAIRE, aValanche phOtodiodes opticaL Time domAIn Reflectometry, is an SBRI funded project, where Pangolin Industries Ltd., supported by the Semiconductor Photonic Devices group, are developing novel near-infrared avalanche photodiodes (APDs) enabling optical time-domain reflectometry. This is, a crucial test and measurement technique, in advanced optical networks and. This metrology is a commonly used in repair and maintenance of existing fibre optical networks.

VOLTAIRE develops APDs to meet an unmet market demand, allowing global test and measurement manufacturers to service and maintain future fibre optical networks more effectively. The semiconductor photonic devices group supports as process architects for the innovative VOLTAIRE chip design, has developed and commissioned device simulation, validated through on-wafer test.

Resonance-Enhanced PCSELs with Mode Control via Perimeter Mirror Design (RE-PCSEL)

Photonic crystal surface emitting lasers (PCSEL) utilise a 2D photonic crystal as the laser resonator in the plane of the epitaxial layers. Due to the finite size of 2D photonic crystal region in a PCSEL light is lost parasitically at the lateral edges of the cavity, also coupled out-of-the-plane of the device as surface emission through first order diffraction. Consequently, the fundamental spatial mode (lowest in-plane loss) with lowest out-of-plane surface loss is the primary lasing mode. For electrically driven PCSELs, as current is increased, incomplete gain clamping results in additional spatial (and spectral) modes leading to a reduction in beam quality. Our new device [REF 3], developed collaboratively with Vector Photonics Ltd., combines comparatively low coupling strength photonic crystal structures along with perimeter mirrors, allow a Fabry–Pérot resonance effect to be realised that provides wavelength selective modification of the photon lifetime for specific modes, providing additional control over mode selection the device and improve light-current characteristics.

Bian, Z., Zhao, X., Liu, J. et al. Resonator embedded photonic crystal surface emitting lasers. npj Nanophoton. 1, 13 (2024). https://doi.org/10.1038/s44310-024-00014-9