Terahertz frequency devices for future communication systems

Summary

High data throughput wireless communication systems are central to our lives and livelihoods. Data traffic is increasing exponentially, with the fastest-growing part of this increase being on wireless channels, as mobile users increasingly make use of online services. This is unsustainable using state-of-the-art radio frequency and microwave systems, and further compounded by the shortage of allocable electromagnetic spectrum into which current radio frequency and microwave wireless communications can grow.

As part of a £7M research programme between the Universities of Leeds, Cambridge and UCL, we are developing the first high throughput wireless communication systems operating at terahertz carrier frequencies for both terrestrial and low-earth-orbit satellite application. These would enable a two orders-of-magnitude increase in data rates over state-of-the-art radio frequency and microwave systems, beyond 100 Gbit/s and towards 1 Tbit/s.

A range of potential PhD projects are associated with this research programme, which can be tailored to the interests and background of the candidate. For example, at the heart of the proposed communication system is the quantum cascade laser (QCL), a semiconductor device comprising more than 1000 separate layers, each patterned with atomic monolayer precision. Edge- and surface-emitting QCLs tuned to atmospheric windows, with suitable output powers, beam quality and operational temperatures need to be developed, and a PhD project in this area would involve the candidate gaining extensive experience in semiconductor device modelling, device fabrication, and electrical and optical characterisation of the lasers. Aligned research projects are available focussing on other aspects of the communication systems including developing new terahertz amplitude and phase-resolved coherent detectors, as well as fast optical and electrical signal modulation methodologies.

These projects would suit an applicant with a good first degree in Physics, Electronic Engineering, Materials Science, or an aligned subject.

Applicants to research degree programmes should normally have at least a first class or an upper second class British Bachelors Honours degree (or equivalent) in Physics, Electronic Engineering, Materials Science, or an aligned subject. Applicants who are uncertain about the requirements for a particular research degree are advised to contact the School or Graduate School prior to making an application.

The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid. Some schools and faculties have a higher requirement.