Atom-based Quantum Photonics

Lead Research Organisation: Durham University
Department Name: Physics

Abstract

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.

Planned Impact

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.
 
Description The goal of this Grant was to provide underpinning support for a range of activities within the Durham Quantum Light and Matter group. The objectives were to use light to understand the behaviour of the atoms and take advantage of opportunities to make optical devices based on our expertise in atom-light interactions. Further, 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). And finally, to incorporate results from our experiments into talks for the public and schoolchildren given by the investigators.

All of these objectives have been met, as outlined below. In addition, a significant other achievement is the training of highly qualified personnel -- more details of which can be found in the Narrative Impact section.
Scientifically we have produced numerous key results, spanning both fundamental physics, greater understanding of atom-light interactions, and producing novel techniques:
Within the topic of Thermal vapours - we studied fundamental physics studying the optical transmission of an atomic vapour in the mesoscopic regime, thus improving the community's understanding of light-latter interaction in the mesoscopic regime. We extended the understanding of dipole interactions in this regime by studying transient density-induced dipolar interactions in a vapour. Our numerous publications on atom-light interactions with vapour subject to external magnetic fields both improved understanding of this key physical principle and found applications in ultranarrow atomic filters. This has led to subsequent grants and broadening of the research portfolio of the research group; more details about nucleation of a new research area are found in the Narrative Impact section.
Within the topic of THz - many key results were obtained, the most significant being Full-field terahertz imaging at kilohertz frame rates using atomic vapor. This field is flourishing, with follow on grants and funding.
Within the strontium work - a significant output is ARC 3.0: An expanded Python toolbox for atomic physics calculations. This has been well received and utilised by the community. The work on Number-resolved imaging of 88Sr atoms in a long working distance optical tweezer is a significant step forward in the burgeoning field of precision atomic clocks based on divalent atoms.
Within the Rydberg activity - significant results in the internationally hot-topic include Enhanced metrology at the critical point of a many-body Rydberg atomic system and Collectively encoded Rydberg qubits.
The theory activity has provided a greater insight into atom-light interactions, with a significant interaction (via a secondment of a PDRA) to one of the world-leading groups in Harvard.
Members of the team participated and led numerous outreach activities, with strong engagement with the public and schoolchildren in the North East.
Exploitation Route The scientific community is already engaged with our work; our papers are highly cited and our codes are being use by other groups.
The work from this grant has led to further grants and funding, in collaboration with other groups.
In July 2022 we hosted a two-day meeting, AQPopen, to bring together researchers from the quantum optics community, and relevant industrial partners. Discussions are ongoing for further applications of our results.
Sectors Aerospace

Defence and Marine

Other

URL https://durham-qlm.uk/
 
Description As identified in the original Case for Support Impact is to be delivered through 4 specific themes: • Long term impact of knowledge generation • Supplying highly-trained personnel • Outreach activities/societal impact • Longer-term impact on international profile of UK research All four themes have (and continue) to be successful. • Details of the knowledge generation are provided I the list of publications, and the Key Findings. • One of the most significant impacts is the training of highly trained personnel. As evidenced in Next Destination 10 post-doctoral researchers were trained with this grant. The vast majority of them have moved on to work in the burgeoning quantum sensing/science/technology field. The documentation for the BEIS 2022 consultation on the UK Quantum Strategy makes it clear that investment in quantum skills will be a high priority. The IoP's report A vision for quantum technologies in the UK calls for "an integrated approach to skills development at every stage, where there are inclusive opportunities for people with different skills, from all backgrounds, to play roles in this new sector, and with a key focus on technical skills, to secure the sector's growth." This grant helped train a large number of PDRAs. • Members of the team participated and led numerous outreach activities, with strong engagement with the public and schoolchildren in the North East. • One of the key outcomes of this project was the emergence of our group as the international leaders for ultra narrow atomic filters. Of particular note is the significant impact the work is having within academia, and potential societal impact. Specifically the use of ultranarrow atomic filters in solar telescopes. Our expertise as world leaders in the field led us to be invited to join an international consortium - SAMNET - with the aim of monitoring the magnetic field on the sun, with the goal of producing earlier predictions of solar storms and weather, which have potential for huge disruption to Earth. The work in this grant led to a large number of high-impact results, which the international community are engaging with. Further, it supported individuals whose work has been recognised as detailed in Awards & Recognition.
First Year Of Impact 2018
Sector Aerospace, Defence and Marine,Other
Impact Types Cultural

Societal

 
Description EU EURAMET proposal "CoCoRiCo" proposal number SRT_FUN_f08_APP1.
Amount £182,480 (GBP)
Funding ID EU EURAMET proposal "CoCoRiCo" proposal number SRT_FUN_f08_APP1. 
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 05/2024 
End 05/2027
 
Description Electromagnetically Induced Transparency with Rydberg Atoms - Towards an Atomic Radio for Wireless Communications
Amount £128,145 (GBP)
Funding ID EP/W009404/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 05/2022 
End 11/2023
 
Description High-speed Terahertz Imaging using Rydberg Atoms & Quantum Cascade Lasers
Amount £666,243 (GBP)
Funding ID EP/W033054/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 06/2022 
End 06/2025
 
Description Quantum optics using Rydberg polaritons
Amount £667,023 (GBP)
Funding ID EP/V030280/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 01/2022 
End 09/2025
 
Description The Solar Activity Monitoring Network
Amount £168,623 (GBP)
Funding ID ST/V006010/1 
Organisation Science and Technologies Facilities Council (STFC) 
Sector Public
Country United Kingdom
Start 09/2020 
End 09/2021
 
Title Data for "Measurement of the atom-surface van der Waals interaction by transmission spectroscopy in a wedged nano-cell" 
Description The data presented in publication "Measurement of the atom-surface van der Waals interaction by transmission spectroscopy in a wedged nano-cell" . Published version: https://doi.org/10.1103/PhysRevA.100.022503 The data are in HDF5 format, with associated metadata. To see examples of how to use the data, and the theoretical model for analysis, see https://github.com/thermal-vapours/TAS-Transmission-Atom-Surface 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
URL https://zenodo.org/record/2653099
 
Title Data for "Measurement of the atom-surface van der Waals interaction by transmission spectroscopy in a wedged nano-cell" 
Description The data presented in publication "Measurement of the atom-surface van der Waals interaction by transmission spectroscopy in a wedged nano-cell" . Published version: https://doi.org/10.1103/PhysRevA.100.022503 The data are in HDF5 format, with associated metadata. To see examples of how to use the data, and the theoretical model for analysis, see https://github.com/thermal-vapours/TAS-Transmission-Atom-Surface 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
URL https://zenodo.org/record/2653100
 
Title ARC 3.0: An expanded Python toolbox for atomic physics calculations 
Description ARC 3.0 is a modular, object-oriented Python library combining data and algorithms to enable the calculation of a range of properties of alkali and divalent atoms. Building on the initial version of the ARC library (Šibalic et al., 2017), which focused on Rydberg states of alkali atoms, this major upgrade introduces support for divalent atoms. It also adds new methods for working with atom-surface interactions, for modelling ultracold atoms in optical lattices and for calculating valence electron wave functions and dynamic polarisabilities. Such calculations have applications in a variety of fields, e.g., in the quantum simulation of many-body physics, in atom-based sensing of DC and AC fields (including in microwave and THz metrology) and in the development of quantum gate protocols. ARC 3.0 comes with an extensive documentation including numerous examples. Its modular structure facilitates its application to a wide range of problems in atom-based quantum technologies. 
Type Of Technology Software 
Year Produced 2021 
Open Source License? Yes  
Impact Used by numerous international groups 
 
Title Quantum and Nonlinear Effects in Light Transmitted through Planar Atomic Arrays 
Description This DOI contains code used to produce the results in the referenced paper. The code calculates light scattering from ensembles of interacting atoms using linear, semiclassical, and quantum models. 
Type Of Technology Software 
Year Produced 2020 
Open Source License? Yes  
URL https://zenodo.org/record/3924699
 
Title Quantum and Nonlinear Effects in Light Transmitted through Planar Atomic Arrays 
Description This DOI contains code used to produce the results in the referenced paper. The code calculates light scattering from ensembles of interacting atoms using linear, semiclassical, and quantum models. 
Type Of Technology Software 
Year Produced 2020 
Open Source License? Yes  
URL https://zenodo.org/record/3924698
 
Description Celebrate Science 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Celebrate Science is Durham University's annual three-day science festival; it celebrates Durham University's latest research with our local community, targeting 7 to 11 year olds and their families. Each year during the local schools' October half-term holiday more than 200 staff and student volunteers from departments across the University engage and inspire young people.
In 2022 over 6,000 people visited the 'Celebrate Science' marquee.
PDRAs and Investigators form this grant were involved in an activity to explain atoms, polarised light, and spectra.
Year(s) Of Engagement Activity 2018,2019,2022,2023
URL https://www.dur.ac.uk/celebrate.science/
 
Description Christmas lecture 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact The Physics Christmas Lecture 2023, "Decoding the Spectrum: Saving Civilisation from Solar Storms" was presented by the PI of this grant. Over 400 local school children attended, and some postgraduates, and others online.
It was a chance to explain to the public how our expertise on ultranarrow filters - supported by this award - has allowed us to make contributions to a solar physics activity, specifically helping to predict solar storms.
Year(s) Of Engagement Activity 2023
URL https://www.youtube.com/watch?v=hvYxLrImEP4