Atom-based Quantum Photonics

The goal of this Platform Grant is to provide underpinning support for a range of activities at the Durham node of the Joint Quantum Centre (JQC) Durham-Newcastle. These are in the general area of the interaction of atoms with electromagnetic radiation (in our case, mostly visible light and near infrared, extending into the ultraviolet, microwaves and terahertz). The physical systems we study consist of either gas atoms in a heated container, or atoms cooled with lasers to within a millionth of a degree above absolute zero. They offer perfect opportunities for the detailed study and exploitation of quantum mechanics, in an accessible and easily controllable way. In addition to using light to understand the behaviour of the atoms, we have taken advantage of numerous opportunities to make optical devices based on our expertise in atom-light interactions.

This Platform Grant will enable us to build on our existing strengths by bringing together individually successful research themes and techniques. This requires a hybrid approach where currently separate experimental themes are brought together, made to work simultaneously, and extended into the quantum regime. Our vision for this adventurous challenge is to develop novel techniques within the domain of atom-based quantum photonics, with the aim being to make and manipulate photons (the elementary particle, or quantum, of light).

The 21st century has witnessed an explosion of research activity into manipulating individual quantum entities (single atoms, single ions, single photons...). This theme was the subject of the 2012 Nobel Prize in Physics, see http://www.nobelprize.org/nobel_prizes/physics/laureates/2012/. One of the most significant breakthroughs is the realisation that the mysterious quantum property of entanglement in addition to being at the heart of Einstein's "spooky action at a distance" was also a resource for the emerging field of quantum information processing. There is a drive towards harnessing the properties of single quantum entities such as qubits in a quantum computer, which could yield computing devices with unprecedented power exploiting the exponential scale up of complexity in a quantum system. Photons are the ideal mediators of quantum information between different nodes of a quantum device, and to interface with atoms in a quantum memory.

The results from our experiments will be incorporated into talks for the public and schoolchildren given by the investigators.

We believe that the research supported by this Platform Grant will have impact through many routes, some of which are short term and others long term:

1. Long term impact of knowledge generation.
The ideas outlined in our proposal are primarily, although not exclusively, of a fundamental, curiosity-driven science character. Thus the standard pathways to academic impact are via journal publications, conference presentations, seminars, and the like.
Much of our research can be categorised as providing basic underpinning science for the heavily promoted quantum technologies agenda. Such underpinning science is an essential base upon which engineering and implementing of future quantum technologies can be built, and the JQC provides and outstanding training environment to produce the personnel necessary for this enterprise to succeed. We achieve this training environment through frequent collective activities, including seminars, and regular group meetings where postdocs and students present and discuss their work.
In the field of "Quantum Physics for New Quantum Technologies" a major issue is scalability; thus there is a drive for miniaturization of devices. In the context of our proposal this means developing and fabricating bespoke optical devices based on compact atomic vapour cells. There already exist many devices which exploit vapour-cell technology, including frequency references, magnetometers, gyroscopes, frequency stabilization and atomic sensors for accelerometers and gravimeters. We will be mindful of opportunities to exploit any potential industrial applications of our research. Future quantum technologies are also likely to use atomic ensembles in quantum memories and quantum repeaters. The fact that the photons produced by atom-based single-photon sources are well matched to resonance lines of atomic vapours means that our work has potential impact in this field.



2. Supplying highly-trained personnel.
One of the significant routes via which impact will be achieved from this staff-centric proposal will be the through the training of personnel: largely the post-doctoral research assistants, and in addition postgraduates and undergraduates associated with the activity.
The researchers involved in the project will gain expertise in state-of-the-art laser techniques, photonics, computer modelling, computer interfacing, and use of analysis software, in addition to generic transferable-skills training.
We are very proud of our tradition of including undergraduates in our research activity, with internship places funded from a variety of schemes, including Durham University, EPSRC, BP, IASTE, and the Ogden Trust.

3. Outreach activities/societal impact.
We have a longstanding commitment to school outreach and public engagement, which we will continue with this project. This will take the form of activities at science festivals, school visits, hosting school visits to the laboratory, Saturday Morning Physics, and public lectures: for example, the JQC-organized public lecture and talk to local school children in 2014 by Nobel Prize Winner in Physics Professor Bill Phillips.

4. Longer-term impact on international profile of UK research.
We are hosting international meetings and conferences with increasing frequency, aided by highly professional in-house events coordinators (such as Event Durham), which raises the international profile of UK research, science and technology. As part of this Platform Grant we will organise and host a two-day meeting, AQPopen, to bring together researchers from the quantum optics community, as well as representatives of the UK National Quantum Technology Programme.