H600 PhD Electrical and Electronic Engineering

Lead Research Organisation: University of Nottingham
Department Name: Faculty of Engineering

Abstract

This project is to design and implement novel ultrasonic transducer technology at the end of optical fibres for the measurement and detection of flaws and disease in engineering and biomedical applications. The aim is to be able to access harder-to-reach areas through the use of narrow optical fibres and endoscopic technology. This will be based on our novel ultrasonic cell imaging technology* and the project will be based around implementing this on optical fibre, the development of novel scanning and imaging systems and application in diverse areas. The project will also explore the implementation of these systems using conventional CW detection technology as well as pump-probe technology.
* Pérez-Cota et al, Appl. Opt. 54, 8388-8398 (2015)

Publications

10 25 50
publication icon
La Cavera S (2019) Time resolved Brillouin fiber-spectrometer. in Optics express

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/N509309/1 01/10/2015 30/09/2020
1811178 Studentship EP/N509309/1 01/11/2016 15/12/2020 Salvatore La Cavera III
 
Description Sound is an incredibly useful tool for probing, and even imaging, a wide range of objects; for example, our research group has used ultrasonics to map features on objects as large as a biscuit tin, and as small as living cells. From an energy standpoint, sound is far less damaging than light, which makes it a great candidate for inspecting living things, as countless pregnant mothers will attest to. Sound can also reach places where light cannot, such as deep into metals, which allows inspection of the object's mechanical properties. Our lab has developed an advanced method of ultrasound imaging called "phonon microscopy." This technique has proven capable of imaging living cells in 3 dimensions and displays "colours" in the form of changes in mechanical properties such as cell stiffness and the local speed of sound, among other qualities.

My project has sought to leverage these developments to be able to deploy such technology onto the tip of an optical fibre, which would vastly expand the range of ultrasonic sensors. Phonon microscopy is a form of laser ultrasound, i.e. lasers are used to generate and detect ultrasound within the sensor. My key findings to-date have been material-related, that is, which materials are suitable for creating these laser-based sensors, and how does their performance and laser-survivability change over time? We have primarily researched the applicability of coloured polymers, and exotic structures called superlattices, in creating the optical fibre sensors. If we use the analogy of a "bell", both materials have proven successful at creating the correct "note," however the repeated impact of the clapper/hammer ultimately destroys the sensor. In the case of the superlattice structure, the bell is completely impervious to the hammer.

Current work has centred around finding a material which better withstands the environment created by laser absorption and heating. One such class of materials are polymers containing carbon nanotubes. These have already proven successful at surviving the onslaught of light and heat, and now their mechanical properties are being investigated and honed. The successful realisation of my project would be, deploying a robust sensor onto an optical fibre, and being able to ultrasonically inspect cellular media within the human-body, or perform inspection on hard-to-reach industrial components.
Exploitation Route The technology is very much still in the developmental phase, therefore considerable work will continue and need to continue going forward before its merits can be applied to real-world problems. The primary investigation of this project has been focused on the fundamentals of the sensor itself and translating and modifying previous technologies to an optical fibre. Once this has taken place, in a way that is stable over months rather than minutes, there will be a need to develop the supplemental components and features, such as lateral resolution, creating an acoustic focus, mounting the device within standard medical equipment, etc. This project is very promising for application in non-destructive evaluation tasks in both industrial and biomedical applications. A sensor that has been supplemented with user-friendly features, could eventually be used in an endoscope to inspect/image cells inside the human body, or inside a cooling hole in an engineering component.
Sectors Aerospace, Defence and Marine,Healthcare,Manufacturing, including Industrial Biotechology,Pharmaceuticals and Medical Biotechnology,Other

 
Description Laser Ultrasonics International Conference 2018 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact This was an international conference for the field of Laser Ultrasound, which our university (The University of Nottingham) hosted. I presented a talk on my research for 15 minutes, and also presented a poster on a separate topic and fielded questions. The event allowed the opportunity for me to better integrate into the research field, and potentially identify like-minded projects/researchers which could be of use in a collaborative or assessor capacity in the future.
Year(s) Of Engagement Activity 2018
URL http://lu2018.iopconfs.org/home
 
Description Technology Transfer (RCNDE) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact This event was organised (by the RCNDE branch of the EPSRC) in order to present and disseminate engineering research to an audience of industrial sponsors, all of whom were affiliated with the RCNDE. I presented a 5 minute talk to the audience, and later presented a research poster; I was also able to network with quite a few industry persons.
Year(s) Of Engagement Activity 2016,2018