Counterfeit products, particularly cloning of different electronics devices, are emerging as a significant problem in many industries and technologies. One way to approach this problem is to create Physical Uncloneable Functions (PUFs). They are a relatively recent invention providing an alternative method to generate secrets for unique identification or cryptographic key generation. Instead of storing the secret in digital memory, or asking a user to provide it, it is derived from a physical characteristic of the system. The assumption is that the secret cannot be copied, as it is bound to a physical entity which cannot be cloned. Furthermore, it is assumed that the probability of finding two devices with identical physical characteristics is very low. Hence, using this atomistic variability could create unique fingerprints which can be used to securely and precisely identify a specific device or an object.

As a result, PUFs have the potential to revolutionise the way that resource-constrained (e.g. IoT) devices are authenticated. When compared to existing solutions they offer small footprints, use fewer resources and provide much greater security. Existing demonstrations of PUFs have been limited, however, and results are constrained by statistics. A lack of validation through large-scale testing or simulations is a significant barrier to adoption. Hence, one of the aims of this proposal is to address this issue.

In this fellowship, two possible structures will be explored as a PUF: a Resonant Tunnelling Diode (RTD) and a Single Electron Transistor (SET). Both devices encapsulate a quantum nanostructure. RTDs and SETs display an exotic I-V characteristic not seen in classical devices, with the nanostructure only allowing electrons to exist at well-defined energy levels. Current can only flow through the device at these energies, thus, this type of devices allows current to flow only at well-defined voltages. These voltage peaks are highly dependent on the quantum confinement exhibited within the nanostructure, which is subject to the overall atomic arrangement of the device. Hence, the device output is directly linked to atom-scale variations and could be used as unique 'fingerprints' to distinguish each device. Moreover, the devices at the heart of this proposal (RTD and SET) are compatible with the current CMOS technology. It can be manufactured from a wide range of materials, at different scales and in different configurations. However, finding the optimal design for incorporation into existing fabrication processes by trial and error would be time consuming and expensive. This is a significant barrier to exploitation of those devices. Hence, the other aim of this fellowship is to overcome this significant barrier by combining theory and simulations with experiments, addressing fundamental issues and providing insight that leads to improvement of the fabrication processes.

This project brings together three UK company and one research groups in the University of Glasgow to deliver progress in the field of improving the design parameters and performance of RTDs and SETs for a specific PUF application.

Potential Impact:
(1) Societal benefits: education and training
The collaboration and interaction between various researchers from academia and the industry proposed in this application will yield great potential teaching and research benefits for the students and the University of Glasgow itself. This is because the Fellow plans to hire one post-doctoral researcher (PDRA) and to apply for additional funding to work with at least one Ph.D. student. The student and the PDRA will participate in multidisciplinary research that will enable them to become highly skilled engineers with a broad range of skills. These people will then train the next generation of researchers and engineers in the field of quantum technology.

Also, this project will help the PDRA to improve his/her public engagement and organisational skills (transferable skills) by allowing him/her to contribute to organising workshops/seminars and managing the group's website. A key feature that I would like to introduce in the project website is a set of learning tools focused at schools and colleges. There is a great opportunity to create educational resources and online computational experiments.

It is clear that many people are confused by what quantum technology can do and what it cannot do. If funded, I propose to develop outreach talks on quantum technology to explain the benefits in simple terms that any non-scientist can understand. For example, I would like to give public lectures at the Glasgow/Edinburgh Science Festival or Cafe Scientifique. Also, within Glasgow, I will work closely on this project with the UK Quantum Technology Hub in Quantum Enhanced Imaging and with the Glasgow Science Centre in order to develop teaching resources for quantum technology. I will engage with these organisations through the Glasgow led Hub to maximise the output.

(2) Economy impact: high tech UK and EU companies
The proposed project combines excellent research with the potential to bring significant dividends to the electronics industry and broader UK economy. The worldwide micro- and nano-electronics market, based principally on semiconductor materials, is currently valued at around $300 billion. Semiconductor components are ubiquitous in everyday life, pervading automotive, medical, industrial and consumer markets as well as data processing and telecommunication sectors. However, advancement in the field requires new materials and device architectures to be translated into new products.

The technologies generated in this research will provide new computational tools and physical models, which could significantly reduce the cost and time of introducing a novel product to the market. Moreover, it will allow the industry and researchers to go beyond the typical semiconductor materials and architectures, which will have a significant impact on research of the 'more than Moore' and 'beyond Moore' technology.

These benefits will be of great interest also to the two UK based SMEs (Quantum Base Ltd. and SemiWise) and spin-offs that supply CMOS foundries and develop niche applications. Quantum Base Ltd. will directly utilise and develop some of the technology to create the next generation Physical Uncloneable Functions. Additionally, the proposed computational tools could have applications in quantum computing, sensors for medical diagnostic and quantum security by significantly reducing the time to market and elaborate the complex scientific and engineering problems in those areas. For example, cyber circuity and global GPS navigation markets are currently worth £65 billion and £21 billion correspondingly. However, the cyber circuity market is expected to reach £164 billion by 2021.

In summary, this fellowship will be helping the UK industry to understand the complex nature of the quantum properties at the nano-scale dimension, which will lead to ensuring that the UK becomes the focal point for this development rather than the US, Japan or South Korea.