OPTOCAP is researching tomorrow’s encryption technology using quantum computing. This company of the ALTER TECHNOLOGY Group, headquartered in Scotland, specialises in the packaging of optoelectronic and microelectronic components used in the aerospace industry. The company is participating in the QUEST project of Glasgow’s Fraunhofer Centre of Applied Photonics (FCAP), which uses satellite technology to research quantum key distribution (QKD) over long distances.
QKD is designed to make communication secure. This is a method of quantum mechanics. It allows two parties to produce a common random secret key that is known only to them. This key can be used to encrypt and decrypt messages between sender and receiver. The technical prerequisites for this are already in place; the process, which has been the subject of research since the 1980s, is developing rapidly and could also be used commercially in the future. However, the devices developed so far for this purpose are based on the transmission of suitable quantum states of light through fibre-optic networks. So, due to fibre loss, the maximum achievable distance is currently only 100 to 200 kilometres. To overcome this limit, initial investigations into satellite QKD are starting. The propagation path runs for only a few kilometres through the atmosphere, which means that hardly any losses are incurred.
This is where QUEST and OPTOCAP, as one of its partners, come in: this technical feasibility study aims to investigate the commercial development of a compact source of polarisation entangled photons for satellite deployment. OPTOCAP wants to take advantage of this market opportunity: “By actually developing and assembling a compact, fully packaged source we aim to define the technical and conceptual challenges in developing such a device, as well as its commercial opportunities,” says OPTOCAP’s Stephen Duffy by way of explanation of the company’s objective. “Ideally, at the end of the project, we will know the way to actual product marketing – or at least be able to define which technological advances still have to be made on the way there.”
QUEST is a feasibility study which is targeting the emerging market of space QKD and is aimed at evaluating the potential of a device for the generation of entangled photons. It (in some of its protocols) directly exploits entanglement to allow the secure share of a cryptographic key for information encoding. This project is therefore perfectly aligned with the competition scope of “entanglement”.
On the one hand, technical feasibility will be assessed by developing, testing and packaging a polarisation entanglement source. This will make it possible to precisely evaluate the resources needed for the eventual commercialisation of the device. On the other, the emerging market of space QKD will be investigated by means of a thorough market study, aimed at evaluating the prospects for success of the proposed device. Further opportunities beyond the space market will also be investigated, e.g. the possible use of the source for line-of-sight QKD through the atmosphere. Also involved will be the identification of a range of possible customers, such as universities or companies willing to enter the QKD market but not interested in developing the source in-house.
This two-fold approach will make it possible to evaluate the cost/benefit of the device, eventually providing OPTOCAP with the information it needs to decide whether to undertake the commercialisation of a source of polarisation entangled photons.
The project will capitalise on both the expertise of the Fraunhofer Centre for Applied Photonics in the design/assembly of optical setups and quantum technologies and Optocap’s expertise in the packaging and testing of optical setups.