Low-loss mid-infrared microstructured optical fibers

About the Project

Supervisory team: Principal Research Fellow, Tonglei Cheng and Associate Professor, Lin Xu

Mid-infrared (MIR) optical fibers are critical for applications such as environmental monitoring, biomedical diagnostics and chemical sensing. This project aims to develop low-loss MIR microstructured optical fibers (MOFs) for efficient light transmission in MIR spectral region (2–20 µm).

Mid-infrared (MIR) optical fibers are critical for applications such as environmental monitoring, biomedical diagnostics and chemical sensing. However, current optical fiber technologies are limited by the transmission window of silica optical fibers (0.3–2.5 µm), which severely constrains the advancement of MIR optical fiber technology. As a result, preventing their use in critical spectral regions such as the molecular “fingerprint” band (2–12 µm) and the atmospheric windows that are essential for gas-molecule sensing, military applications and aerospace operations.

This research will explore chalcogenide and tellurite glass compositions with broad MIR transparency and engineer their microstructured geometries to minimize material and confinement losses.

Advanced numerical modelling will optimize parameters such as core size, air-hole arrangement, and pitch to achieve single-mode guidance and ultra-low attenuation.

Fabrication will employ stack-and-draw or extrusion techniques, followed by rigorous characterization of attenuation, modal properties and mechanical stability.

The expected outcome is a robust fiber platform enabling compact, flexible waveguides for next-generation sensing and spectroscopy systems.

Entry requirements:

You must have a UK 2:1 honours degree, or its international equivalent.

Fees and funding:

Full scholarships include tuition fees, a stipend at the UKRI rate plus 10% ORC enhancement tax-free per annum for up to 3.5 years (totalling £22,858 for 2025/26, rising annually) and a budget of £4200 for things like conference travel. UK, EU and Horizon Europe students are eligible for scholarships. Chinese Scholarship Council funded students are eligible for fee waivers. Funding for other international applicants is very limited and highly competitive. Overseas students who have secured or are seeking external funding are welcome to apply.

For more information, please visit our postgraduate research funding pages.

How to apply:

Apply now

You need to:

• choose programme type (Research), 2026/27, Faculty of Engineering and Physical Sciences
• select Full time or Part time
• search for programme PhD ORC (7097)
• add name of the supervisor in section 2 of the application

Applications should include:

• your CV (resumé)
• 2 academic references
• degree transcripts and certificates to date
• English language qualification (if applicable)