Light-matter interactions and quantum photonics in nano-scale semiconductor structures and devices

We propose a Centre-to-Centre consortium formed of 10 academics from the University of Sheffield (USHEF) and the Technical University of Dortmund (TUD) to exploit light-matter interactions in advanced materials, achieving agenda-setting advances in non-linear optics, single photon phenomena and spin-control on the nanoscale. We will study ultra-pure cuprous oxide, atomically thin two-dimensional semiconductors, and III-V semiconductor nano-structures, all at the forefront of modern day research. The collaboration provides major added value to the UK by enabling cutting-edge research themes supported by close interaction with highest quality scientists at TUD, as well as access to their world-leading experimental infrastructure.

The interaction of light and matter is at the heart of a huge range of natural phenomena and applications in physics, chemistry, biology etc. In this project, we will use potentially transformative approaches to harnessing these phenomena by using specially designed nano-structured materials, and exploring non-linear and quantum optical phenomena in micro- and nano-photonic structures. The ambition is to seed and develop new research directions based on enhancing and controlling light-matter interactions in nanoscale structures. To this end we will use a broad base of novel materials including atomically thin layers of transition metal dichalcogenides (TMDs), ultra-pure Cu2O, and quantum dots located within III-V semiconductor nano-photonic structures.

The consortium will address three inter-related themes having considerable synergy and sharing of techniques and physics including: non-linear and quantum optics with Rydberg exciton-polaritons in cuprous oxide; valley phenomena in van der Waals heterostructures; ultrafast quantum nano-photonics.

All three themes involve the harnessing of light-matter interactions in novel material systems. Design on the nanoscale is a common theme throughout enabling the discovery of new optical and quantum-optical phenomena. Furthermore, they all rely on the control of the properties of excitons in extreme limits. As well as leading to ground-breaking new physics, the programme has potential to open up long term applications in quantum communications and in spintronic devices to give just two examples.

The highly integrated collaboration programme, exploiting to the full the benefits of the Centre-to-Centre cooperation, will be supported by a total of 60 months of extended visits by postdocs in both directions between Sheffield and Dortmund.

Our Impact strategy will have four main components as shown below.

1. KNOWLEDGE DISSEMINATION WITHIN THE SCIENTIFIC COMMUNITY will be achieved via publications in leading journals including the Nature family, PRL, PRX, Nano Letters etc where all proposers have published extensively in recent years; talks at international conferences and workshops; participation in large-scale UK and international initiatives including (i) the Horizon-2020 FET Graphene Flagship, (ii) UK Quantum Technology Programme through membership of the York Quantum Communications Hub, (iii) EPSRC Photonics Manufacturing Hub, (iv) Horizon-2020 MSCA ITN Spin-NANO, (v) EPSRC Programme Grant in Semiconductor Quantum Photonics led by USHEF (EP/N031776/1), (vi) National Graphene Institute, (vii) Mega-Grant Programmes led by USHEF and TUD respectively in collaboration with research institutions in St Petersburg, (viii) the Quantera EU initiative.

2. KNOWLEDGE AND TECHNOLOGY TRANSFER AND DIRECT ENGAGEMENT WITH INDUSTRY. Our project concerns fundamental research into 2D materials and quantum photonics with strong potential to impact development of quantum photonic circuits, quantum communications, strongly nonlinear optical devices for photonic applications, and logic elements for spintronic devices. At this stage our industrial engagement strategy will consist of establishing and maintaining long-lasting contacts with relevant industry. This will in part be achieved by closely involving, at project meetings and by direct contact, industrial partners with whom we already have close links. They provide a range of specialist knowledge in advanced experimental hardware [Oxford HighQ (Oxford), Chase Research Cryogenics (Sheffield) - both are project partners (see LoS), Attocube (Munich)], materials [Helia (Livingston), HQGraphene (Groningen)], and quantum technologies [Hitachi (Cambridge), Toshiba, IBM (Zurich), Single Quantum (Delft)].

3. TRAINING OF HIGHLY QUALIFIED PERSONNEL We aim to train 3 postdoctoral researchers at USHEF and at least 3 at TUD, as well as several PhD students at both Centres, to high levels in physics, optics, device fabrication during the course of the grant. All these areas are highly relevant industrially and academically. University-wide career coaching will be available in Sheffield through the Think Ahead programme. We will also make arrangements to allow access for the visiting postdocs from TUD to our career coaching courses at Sheffield. The combination of participation in research at a high level, together with the oral, written and organisational skills, as well as direct involvement with the industrial partners, will prepare outgoing members very well for future careers in industry and academia, of considerable benefit to the UK economy. In the last 10 years the large majority of researchers supervised by the investigators have taken up positions in hi-tech industry (~75% with the remaining 25% in academia) including Toshiba, Intel, Huawei, Attocube, AMRC, NPL, showing the range of skill-sets we transfer to our researchers to be much in demand.

4. PUBLIC ENGAGEMENT We will participate in a variety of outreach activities targeting the general public, school pupils and undergraduates. Within the context of the Centre to Centre proposal we will use our recent experiences to create additional videos for the Quantum Light channel including an animation describing the importance of nonlinear photonics in modern and future technology. The postdocs and PhD students from the USHEF/TUD grouping will be encouraged to participate in the production of the new videos and in the planned USHEF exhibit at the Cheltenham festival in 2021. As well as the science festivals, in-line with current practice, the videos will also be employed at university open days and presentations at high schools, providing a further stimulus for the younger generation to engage with science and physics in their future lives and careers.