Pierre Maidment 

I joined the CDT in September 2017 after completing a Physics Master’s degree at the University of Manchester.  

Project Title: Development of a multispectral laser scanner in silicon photonics

Supervisors: Prof. Marc Sorel at the University of Glasgow 
Secondary: Dr Amit Kumar at QUB 

Project description: A silicon photonics platform is ideal for confining and guiding light of a large wavelength range. We use this platform to develop a phased array antenna in order to steer beams of different wavelengths across an object simultaneously and subsequently record the absorption of the beams to reveal properties such as moisture content. The phased array consists of single-mode waveguides along with sharp 90-degree bends, 3dB power splitters and thermo-optic phase shifters that all support low-loss transmission for a wide wavelength range from the O- to C-bands. A compact multi-wavelength laser scanner could be used in any setting from soil to space to replace more time-intensive processes. In agriculture, for example, the sensor can be used in testing product quality and areas of fields requiring attention such as water or selective distribution of certain nutrients or pesticides. 

The device is the first step to a fully-functional and compact multispectral laser ranging device utilising lidar techniques. The lasers can be coupled into the array through transfer printing or flip-chip bonding of the laser dies. The chip will also consist of on-chip photodetectors with a receiving waveguide array and scalable, CMOS-compatible electronics capable of delivering power supply to the heaters and frequency modulation of the input laser signal. Range and velocity information can be determined by comparing a portion of the chirped input signal with the received reflected signal. 

General Research/Science Interests: 
During my undergraduate studies I took specialised modules in lasers, image processing, photonics and semiconductors so the CDT and this project naturally drew my interest. I also enjoy reading about the latest developments in the fields of nuclear and particle physics, magnetism as well as medical imaging techniques including PET and CT scans which were the subject of my Master’s research. 
 
Impact Activity:  
I thoroughly enjoyed hanging out as a cohort in first year and partaking in a lot of varied activities outside of the core modules. Since then I have joined others in planning and broadcasting an engineering-focussed radio show, helping out at science fairs and visiting a local primary school showing how our research is used in every day devices. I have also assisted in lab demonstrations to visiting school students and maths tutorials to undergraduates. The opportunity to take part in both CDT and university-organised workshops on thesis and scientific writing skills, project management and coding languages have enormously helped my experimental data collection, organisation and writing up. Finally, the CDT has been very open in welcoming us to attend industrial visits, networking and careers days that have given me a taste of what to expect after the PhD concludes. 

Other interests: 
I love all sorts of outdoor sports including running, cycling and badminton. While other activities have been limited as of late, I also enjoy going to the gym and judo classes. For a more relaxing experience I also play piano, read (mostly John Grisham books) and play games. 

Testimonial: 
I really enjoyed the first year of the CDT programme; hanging out with my cohort was an absolute blast and we remain close despite recent events. My project has so far been challenging but extremely rewarding as I have been mostly allowed to define the scope of the project and shape the direction on my own terms. The CDT has been very supportive through these turbulent times and the bi-annual activities including the Conclave are a great opportunity to present our research and reunite over drinks! 

Contact me: 
p.maidment.1@research.gla.ac.uk