QG-CANE (Quantum Gravity for detection of CAvities from Nuclear Explosions)

About the Project

Nuclear explosions are forbidden by the Comprehensive Nuclear Test Ban Treaty (CTBT), with on-site inspection (OSI) forming the final verification regime for determining breaches. Underground voids, rubble zones and collapsed features associated with “ground zero” of underground nuclear explosion are of interest as they identify the test site and present an opportunity for radionuclide sampling to comprehensively prove the nuclear nature of the explosion. However, these remain challenging to detect using geophysical techniques permitted by the treaty, as they are relatively deep features that may be located several 100m below the ground surface.

Gravitational field mapping is one technique which can be used, which has the advantage of being a passive technique, giving it a good opportunity to see deep targets. However, current spring-based field gravimeters are limited both by their resolution and by sources of environmental vibrational noise superimposed on the measurements. QT gravity gradient sensors based on atom interferometry promise both a far greater resolution, lower drift absolute sensing capable of time lapse surveying and the ability to supress environmental noise, creating a sensor useful in field applications such as during an OSI.

This PhD project investigates the use of novel quantum technology gravity sensors with higher sensitivity and lower noise characteristics than current gravimeters to identify underground cavities and collapse zones and their development over time within the framework of a CTBT on-site inspection. Computer simulations will be used to quantify the increased detection capability of the new sensors, the optimum configuration for deployment and the potential to detect progressive changes over time, thus helping with treaty enforcement. Alongside, field trials will be undertaken using both classical gravimeters and QT gravity gradient sensors.

This project is part of the QG-CANE (Quantum Gravity for detection of CAvities from Nuclear Explosions) project. The successful candidate will be based in the School of Engineering at the University of Birmingham and linked to the Quantum Technologies Research Hub in Sensing, Imaging and Timing (QuSIT, www.qusit.org), having access to advice and support from a wider team of world leading experts on the development of quantum gravity instruments for field applications. The quantum technologies research at the University of Birmingham involves researchers based in engineering, physics and astronomy and environmental sciences addressing the development of sensors and their applications. The School of Engineering comprises civil, mechanical and electrical engineering and is host to the National Buried Infrastructure Facility (NBIF, www.birmingham.ac.uk/nbif) which allows us to create controlled environments to evaluate, amongst others, quantum technology sensors. Furthermore, the student will be introduced to other members of the CTBTO OSI community and key stakeholders thus providing a useful network for advice and discussions on the practical focus of the work.

Entry requirements

This opportunity is open to UK students only.

The successful candidate should be highly motivated and keen to work across disciplines to solve complex problems. Applicants should have:

• a good primary degree (First- or Upper Second-class Honours) or MSc in an engineering, physics, geophysics or mathematics discipline. A relevant masters degree and/or employment experience would be an advantage.
• Strong mathematics, numerical modelling and data processing skills.
• Good written and verbal communication
• Interest and enthusiasm for the subject, a willingness to learn, and the ability to think creatively about complex geophysical problems and sensors.
• An individual keen to drive the quantum technologies agenda forward and engage with the wider community
• Ability to produce high-quality presentations and written reports.

Funding Notes

This opportunity is open to UK students only. This project is offered through QG-CANE, funded by the Quantum Centre for Nuclear Defence and Security at AWE. Funding covers: annual stipend, tuition fees for home students.