Diamond in Advanced Technology with Optical Machining (DIATOM)

Lead Research Organisation: University of Oxford
Department Name: Engineering Science

Abstract

For centuries diamond has been highly sought after for manufacture into gem stones; the demand stems from its exemplary physical properties. Such remarkable characteristics also render diamond a promising host medium for many advanced technology applications. With recent breakthroughs in the manufacture of synthetic diamond substrates, the adoption of diamond into widespread device application is becoming ever more tangible. However, there is an urgent need for a scalable processing framework that can turn this hard, inert material into functional devices. In the course of this fellowship, I will develop a diverse toolkit based around laser fabrication which can fill this void. Through the use of short pulsed lasers and advanced optical techniques, accurate fabrication in three dimensions beneath the surface of diamond becomes possible.

Dependent on the laser power and how it is focused into the diamond, different processing regimes are possible. Electrically conductive wires may be printed in 3D running through the diamond, as can optical wires for routing light through the diamond. By reducing the laser power, it is possible to introduce just a single defect in the diamond lattice which can then be used as an information bit for quantum processing. Devices manufactured will include detectors of high energy radiation for use at CERN, 3D arrays of defects for quantum enhanced sensing and 3D photonic structures for manipulation of light. This will deliver a route to commercial diamond technology as well as a set of optical fabrication protocols that are transferable across wide technological areas.

The bulk of the work will be carried out at the Department of Engineering Science at the University of Oxford. There will be close collaboration though with partners at the Universities of Manchester, Warwick and Strathclyde, harnessing their unique capabilities to develop a complete photonics system for the creation of advanced technology devices in diamond.

Planned Impact

Scientific impact will be achieved through the use of advanced photonic processing to manufacture functional diamond devices, targeting key applications. The demonstration of device architectures that were previously impossible, providing enhanced functionality and performance will generate impact. Applications specifically outlined in the proposal include radiation detectors, defect arrays for quantum enhanced sensing and photonic devices.

I will additionally work with researchers in the UK and around the world to replicate the photonic system, which will enable proliferation of the technology and maximise impact. I am already actively pursuing this, by working with project partners University of Manchester to develop an advanced optical fabrication system purely for the manufacture of radiation detectors. This spread of the developed technology will aid those working in diamond science and other diverse disciplines, including biophotonics, metamaterials and medical technology.

There will be further scientific impact at a more fundamental level. This work is already pushing the boundaries of optical processing. The ability to induce single Angstrom level material modifications through fabrication with light at optical wavelengths is revolutionary. Furthermore, this probes the fundamental light matter interaction at high resolution, and can inform on material properties at the nanoscale.

Impact is also gained through collaboration. This fellowship will bring together UK scientists with a diverse skill set, and will use their expertise in new ways to solve difficult problems across a range of applications. International collaboration is specifically arranged to in crease the spread of ideas and technology.

Commercial impact from this work can be expected as the scientific impact gains recognition. I am already working with four separate companies on the application of laser processing for diamond devices. This can be expected to increase through the fellowship as the technology becomes more established. Key industrial links with Oxford Lasers Ltd and Element 6 are specifically included in the fellowship to aid the commercialisation of the technology.

The inherent appeal of diamond to the general public leads to many opportunities for outreach. As a member of the Early Career Outreach network at the University of Oxford, there are lots of opportunities to share ideas with members of the public and I will introduce ideas related to diamond technology. Further impact will hopefully be provided by helping to get more people across the UK interested in science and engineering.
 
Description We have extended the use of laser written graphite conductors embedded inside diamond to new applications and new device designs. New research networks have been set up with Diamond Light Source, UCL, Princeton and Cadiz to exploit these advances.

We have also shown how laser processing can be used to deterministically create single defect colour centres inside diamond that are useful for quantum technology. These can be fabricated in an all-optical process at very high yield, and display excellent coherence properties.

New avenues of research and technology have been opened up by transferring techniques developed in the award to new field, particularly in the manufacture of calibration devices for microscopes, liquid crystal photonics and integrated optical feedback during laser manufacturing.
Exploitation Route There are many new directions for the research in embedded graphite electrical conductors. Work is still needed to fully understand the conduction mechanism and correlate with the structural modifications. These can then be taken forward to optimise device performance and design. These advances can then be expected to translate into industrial use of such devices.

The laser written colour centres developed in this award has opened up a new research field which is being pursued by multiple international research groups. Work is focusing on analysis of the colour centres and incorporation into external architectures appropriate for quantum information processing. Work is also being pursued to fabricate new defects and to control defect density. Our techniques are patented and licensed and we are starting to see industrial adoption.
Sectors Digital/Communication/Information Technologies (including Software)

Electronics

Manufacturing

including Industrial Biotechology

 
Description This award has developed a range of advanced optical techniques for laser manufacturing. Whilst the award was directed towards the manufacture of diamond devices, the findings from the award have had far broader impact in laser manufacturing for many different application areas, covering quantum technology, optical fibre sensors and bioimaging. The developments are driving further academic research and starting to filter through to industrial and societal impact. An important stream of work through the award was the development of laser written fluorescent slides for calibration of microscopes used in biological imaging (PSFCheck). These slides are laser machined at precision, and with project partner University of Exeter supplied at cost to international research labs and companies. The PSFCheck calibration slides enable better comparison of results taken on different microscopes at different research centres brining a greater level of repeatability to the community and ultimately benefitting society through increased confidence in data. An additional important impact arising from the award is the development of laser security marking for gemstones. This has been commercialised through associated spin-out company Opsydia, who are providing machines to international customers. Subsurface laser written identifiers can now be found in many commercial diamond gemstones, providing a secure record of provenance and quality, without affecting the optical grade of the stone. This benefits both the UK economy through employment in advanced manufacturing, and the consumer sector who can now have more confidence in their purchased goods.
First Year Of Impact 2017
Sector Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software),Manufacturing, including Industrial Biotechology,Security and Diplomacy
Impact Types Societal

Economic

 
Description EPSRC Early Career Forum in Manufacturing
Geographic Reach National 
Policy Influence Type Membership of a guideline committee
URL https://ecfmanufacturing.com/
 
Description EPSRC Capital Award in Support of Early Career Researchers
Amount £34,312 (GBP)
Funding ID EP/S017658/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 02/2019 
End 03/2020
 
Description Multiscale multidimensional integrated imaging for precision laser processing (M2I2)
Amount £863,618 (GBP)
Funding ID EP/W025256/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 11/2022 
End 11/2025
 
Title Fluorescence calibration specimen 
Description This is a tool which is useful in the alignment and calibration of fluorescence microscopes, which are widely used for biological imaging. We use a laser fabrication process to accurately write fluorescent structures inside a plastic sample. This tool can save system time and improve the quantitative analysis of images. 
Type Of Material Improvements to research infrastructure 
Year Produced 2018 
Provided To Others? Yes  
Impact This tool has been fabricated and delivered to numerous different research groups in the UK and abroad, who are using it for routine alignment and calibration of their microscopes. 
URL http://www.psfcheck.com
 
Description Electrical devices in diamond 
Organisation University College London
Department Department of Electronic and Electrical Engineering
Country United Kingdom 
Sector Academic/University 
PI Contribution Laser fabrication of electrical devices in diamond for sensing in harsh environments.
Collaborator Contribution Device design and testing
Impact Paper published in ACS Nano on diamond electrical devices, laser written at Oxford with electrical analysis at UCL and structural characterisation by Transmission Electron Microscopy at University of Cadiz, Spain. doi: https://doi.org/10.1021/acsnano.3c07116 . A related patent application has also been submitted on the fabrication of embedded diode structures in diamond (UK PATENT APPLICATION NUMBER 2303700.5, March 2023).
Start Year 2021
 
Description Heriot-Watt 
Organisation Heriot-Watt University
Department Physics
Country United Kingdom 
Sector Academic/University 
PI Contribution Laser processing inside silicon carbide substrates for applications in quantum technology
Collaborator Contribution Measurements on devices, lithography of substrates prior to laser manufacture
Impact Paper published on laser engineered defects inside diamond: https://doi.org/10.1103/PhysRevApplied.21.024026
Start Year 2021
 
Description University of Exeter 
Organisation University of Exeter
Country United Kingdom 
Sector Academic/University 
PI Contribution My team uses advanced laser fabrication techniques to manufacture devices for the calibration of fluorescence microscopes.
Collaborator Contribution The team of Alex Corbett at the University of Exeter carries out quality control analysis of the fabricated devices and organises distribution to interested parties.
Impact The partnership is multi-disciplinary, bringing together expertise in bioimaging and laser processing. The results of the collaboration have been presented at international conferences and in the following papers: 10.1364/OE.26.021887; 10.1364/boe.389904; 10.1364/BOE.10.005611 As part of the PSFCheck initiative, we distribute devices for accurate calibration of biological microscopes. The devices are distributed via University of Exeter and provided at cost. To date, over 200 devices have been distributed to users in industry and academia. This feeds into a community desire and need to monitor data reliability and reproducibility in biological imaging.
Start Year 2017
 
Description University of Manchester 
Organisation University of Manchester
Country United Kingdom 
Sector Academic/University 
PI Contribution My team at the University of Oxford uses advanced laser fabrication techniques to manufacture arrays of graphitic wires inside diamond substrates for use as detectors of high energy particles.
Collaborator Contribution The team at the University of Manchester provide designs for the devices and interfaces the laser written wires with read-out electronics. They also provide access to sources of high energy particles for device testing and analysis.
Impact The collaboration is multi-disciplinary, combining expertise in particle physics (Manchester) with laser manufacturing at Oxford. The collaboration has produced >5 prototype devices that have been tested. Results have been presented at international conferences and in 4 publications: 10.1016/j.diamond.2017.06.014 and 10.1016/j.nima.2016.04.052; 10.1016/j.diamond.2020.108164; 10.1016/j.nima.2019.162675. Through this work, I was invited to join the RD42 collaboration at CERN in June 2022. I am responsible for the laser processing of the 3D diamond detectors, which are scheduled to be installed in the BCM' detector as part of the LHCb upgrade.
Start Year 2016
 
Description University of Warwick 
Organisation University of Warwick
Country United Kingdom 
Sector Academic/University 
PI Contribution This collaboration is exploring the use of laser writing for fabrication of diamond devices for quantum technology. My team is engaged in the laser fabrication of nitrogen vacancy qubits inside the diamond.
Collaborator Contribution The laser written diamond devices are processed and analysed by the team at University of Warwick under the supervision of Dr Gavin Morley and Prof Mark Newton. The processing constitutes high temperature annealing while the analysis incorporates a range of fluorescence microscopy.
Impact This collaboration is multi-disciplinary, combining laser fabrication expertise at Oxford with quantum technology expertise at Warwick. The collaboration has resulted two high impact papers 10.1103/PhysRevApplied.12.064005 and 10.1364/OPTICA.6.000662.
Start Year 2017
 
Title LIQUID CRYSTAL DEVICES 
Description A liquid crystal device (400) is provided comprising: a liquid crystal layer having a thickness and comprising: a liquid crystal material; and a plurality of polymer structures (414a, 414b) comprising polymerised liquid crystal material. Each polymer structure (414a, 414b) is located at a different depth in the thickness of the liquid crystal layer. Electrodes are provided configured to apply an electric field to the liquid crystal layer. Each polymer structure (414a, 414b) has a different selected locked-in liquid crystal state. 
IP Reference WO2023079258 
Protection Patent / Patent application
Year Protection Granted 2023
Licensed Commercial In Confidence
Impact Commercial In Confidence
 
Title Laser Writing for Colour Centres in Crystals 
Description A method of fabricating one or more colour centres in a crystal is described. The method comprises focusing a laser into a crystal to induce the creation, modification, or diffusion of defects within a focal region of the laser. Fluorescence detection is used to determine when one or more colour centres are formed within the focal region and the laser is terminated when a desired number of colour centres have been formed. The method enables colour centres to be formed in a crystal with a high degree of control in terms of both the number and location of colour centres within the crystal, and a degree of control over other parameters such as colour centre orientation and local environment. In particular, it is possible to form a well-defined pattern of colour centres within a crystal. 
IP Reference US2021207287 
Protection Patent / Patent application
Year Protection Granted 2021
Licensed Commercial In Confidence
Impact Commercial in confidence
 
Title METHOD OF LASER MODIFICATION OF AN OTPICAL FIBRE 
Description Method of laser modifying an optical fibre to form a modified region at a target location within the fibre, comprising positioning at least a portion of an optical fibre in a laser system for modification by a laser, applying a correction to an active optical element of the laser system to modify wavefront properties of the laser to counteract an effect of aberration on laser focus, and laser modifying the optical fibre at the target location using the laser with the corrected wavefront properties to produce the modified region. 
IP Reference US2023083093 
Protection Patent / Patent application
Year Protection Granted 2023
Licensed Commercial In Confidence
Impact Commercial In Confidence
 
Title OPTICAL TRANSFORM CHARACTERISATION 
Description A method of determining an optical transform imparted by a multimode optical fibre (300) is disclosed. The wherein the multimode fibre (300) comprises a proximal end, a distal end, and at least one modified region (260) between the proximal end and distal end. The modified region (260) is configured to transmit light toward the proximal end in response to light propagating through the multimode optical fibre (300) from the proximal end to the distal end. The method comprises coupling (101) forward propagating light into the proximal end of the multimode optical fibre; detecting (102), at the proximal end, backward propagating light transmitted from the at least one modified region in response to the forward propagating light; and determining (103) an optical transform from the detected backward propagating light. 
IP Reference US2024049950 
Protection Patent / Patent application
Year Protection Granted 2024
Licensed No
Impact The invention is currently being applied in our research labs through PhD research to demonstrate potential in industry.
 
Company Name Opsydia 
Description Opsydia develops technology to fabricate diamond structures using lasers. 
Year Established 2017 
Impact Opsydia technology is being adopted by one of the world's leading diamond groups, De Beers Group, as part of its new lab-grown diamond initiative, Lightbox Jewelry. The subsurface laser marks both prevent the stones used in the jewellery from being passed off as natural, and serve as a guarantee of quality. Opsydia won the 2019 Start-up Award from the Institute of Physics Business awards in October 2019. Opsydia won the Oxford Innovation Startup Award at the 2019 Oxford Trust Enterprise Awards in September 2019.
Website http://www.opsydia.com
 
Description Quantum Showcase 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact We ran a stand at the UK National Quantum Technologies Showcase, where delegates could learn more about the laser writing technique applied to diamond quantum technology. Delegates were able to remotely control the laser fabrication system in Oxford to write their own quantum bit inside a piece of diamond. More than 100 qubits were successfully written. The event helped to raise awareness of the fabrication technique among the the UK industrial quantum community.
Year(s) Of Engagement Activity 2018
URL http://uknqt.epsrc.ac.uk/news-and-events/events/