Atomically Thin Oxides for Ultralow Power Non-volatile Memory Technology

New high-performance, ultralow power non-volatile memory (NVM) technology is essential to a wide range of diverse and hugely growing data centric technologies spanning IoT, transport, medicine, security, entertainment, neuromorphic computing, and AI, all which will evolve significantly over the next decade, and in time will radically change the way we live. NVM is also essential for strongly improving the efficiency of energy-hungry data centres where memory accounts for a large fraction of the overall power usage. Memristors can mimic artificial neurons capable of both computing and storing data, and they have the potential to dramatically reduce the energy and time lost in conventional computers. Within the memristor structure itself, certain oxides (inc. TiO2 and HfO2) are excellent active layers, owing in part to labile oxygen vacancies affecting the resistance of the layer, upon an applied voltage. This project shall explore and focus on precisely engineered two-dimensional (2D) oxide materials to develop novel active 'switching' layers in memristors. This offers exciting potential for the following reasons: Firstly, we can downscale the overall design, making it more compact and avoid the 'short channel' effect, by confining electrons within the atomically-thin active region. Secondly, we can test novel van der Waals bound active layers where there could be new phenomena giving rise to enhanced switching. Lastly, the large range of available layered materials provides scope to explore a wealth of potential combinations as a multi-layered active layer. Guided first by a material down-selection process, we shall fabricate devices and characterise them using state-of-the-art facilities, all the while considering future potential use cases, with a special emphasis on neural network/machine learning applications.

Our main impacts will be:
- a new generation of interdisciplinary nano researchers with expertise across science and innovation, fluent in the combination of approaches and technologies
- strategic developments in the study and control of nano-interfaces connecting complex architectures, for advances in emerging scientific grand challenges across vital areas of energy, health and ICT
- integration of new functional nanotechnologies together by harnessing nano-interfaces within larger application systems, and their translation into innovative products and services through our industry partners and student-led spin-outs
- a paradigm change of collaborative outlook in this science and technology
- a strong interaction with stakeholders including outreach and public engagement with cutting edge nano research
- improved use of interdisciplinary working tools including management, discipline bridging and IT

Economic impact of the new CDT is focused through our industrial engagement programme, as well as our innovation training. Our partner companies include - NPL, Hitachi, Oxford Nanopore, TWI, ARM, Eight19, Mursla, Britvic, Nokia Bell Labs, IBM, Merck, Oxford Instruments, Aixtron, Cambridge Display Technologies, Fluidic Analytics, Emberion, Schlumberger, Applied Materials and others. Such partnerships are crucial for the UK to revive high value manufacturing as the key pillar to lead for future technologies. We evidence this via the large number of CDT projects resulting in patents, with their exploitation supported by Cambridge Enterprise and our Industry Partners, and direct economic impact has also resulted from the large proportion of our students/alumni joining industry (a key outcome), or founding startups including: Echion Technologies (battery materials), Inkling Cambridge (Graphene inks and composites), HexagonFab (2D materials), Simprints (low-cost biometrics), Cortirio (rapid diagnosis of brain injury).

Training impact emerges through not just the vast array of Nano techniques and ideas that our cohorts and associated students are exposed to, but also the interdisciplinary experience that accrues to all the academics. In particular the younger researchers coming into the University are plugged into a thriving programme that connects their work to many other sciences, applications, and societal challenges. Interactions with external partners, including companies, are also strong and our intern programme will greatly strengthen training outcomes.

Academic impact is fostered by ensuring strong coherent plans for research in the early years, and also the strong focus of the whole CDT on study and control of nano-interfaces connecting complex architectures. Our track record for CDT student-led publications is already strong, including 4 Nature/Science, 6 Nature Chem/Nano/Mat, 13 Nat. Comm., with student publications receiving >6000 citations in total, including 16 papers with >100 citations each and high altmetric scores. Students have also given talks and posters at international conferences and won numerous awards/fellowships for research excellence.

Societal impacts arise from both the progression of our cohorts into their careers as well as their interaction with the media, public, and sponsors. We directly encourage a wide variety of engagement, including interaction with >5000 members of the public each year (mostly pre-university) through Nano exhibits during public events such as the Cambridge Science Festival and Royal Society Summer Science Exhibition, and also art-science collaborations to reach new audiences. We also run public policy and global challenges workshops, and will further develop this aspect with external partners. Our efforts to bring societal challenges to students' awareness frames their view of what a successful career looks like. Longer term societal impact comes directly from our engagement with partner companies creating jobs and know-how in the UK.