Long wavelength single photon sources and dotonic molecules

Lead Research Organisation: University of Oxford
Department Name: Oxford Physics


Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.
Description There have been two main findings arising from this project. In the first we showed that by adjusting the hole separation near two coupled photonic crystal cavities we could introduce an optical well which enabled us to control the coupling and splitting between two cavities with unprecedented precision, allowing for the possibility of using this technique to engineer coupled photonic molecules using single quantum dots in the future. The second key finding involved using a photoresist to define an optical cavity in a waveguide structure. This has the advantage of being able to pick an individual quantum dot in the correct spatial position, with the correct spectral profile such that it could couple strongly to the induced cavity mode. Work is ongoing following the end of the grant to improve the Q-factor obtained, and initial results are extremely promising. We have now managed to produce photonic molecules using this technique and a paper on this has appeared in Optics Express. The output was also disseminated in a major international confrerencei n one oral and one invited paper in Chengdu in China in 2018.
Exploitation Route Photonic engineers may well be able to use the findings to design new single photon emitters where the yield for producing strong coupling is enhanced hugely compared to the common method which relies on chance to produce such coupling.
Sectors Digital/Communication/Information Technologies (including Software)


Description Collaboration with Hitachi Cambridge Laboratories on design and production of photonic crystals 
Organisation Hitachi Cambridge Laboratory
Country United Kingdom 
Sector Private 
PI Contribution We make the optical measurements on the photonics crystals.
Collaborator Contribution Hitachi produce the crystals and pay for their production.
Impact All publications which use Hitachi expertise have the authors and institution credited.
Description Produced an animation for use on the Oxford Sparks public engagement website on single photon sources 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact The Oxford Sparks website hosts animations on science generated by researchers in Oxford. This animation deals with single photon sources and is aimed at informing the general public and schoolchildren about the research field and also refers to quantum computing. There are school materials for use by teachers available which supplement the animation and add impact through education.
Year(s) Of Engagement Activity 2016
URL http://www.oxfordsparks.ox.ac.uk/content/our-media