A QKD system is composed of quantum physical devices (quantum sources, quantum channels and quantum detectors) and classical (and well-established) information technology.
Photon Emitters
MIQC will provide a measurement framework for the characterisation of photon emitters developed for QKD. Specific operating parameters will be quantified with known uncertainty, and traceable measurements provided for all relevant QKD source parameters. In detail, MIQC will:
- Develop techniques for traceable measurement of photon emitter statistics
- Deliver measurements of spectral, temporal and polarisation properties of attenuated laser QKD sources
- Evaluate the quantities used by the quantum information community to characterise single-photon sources; this includes parameters such as Γ1, Γ2, g(2)
Quantum channels
MIQC will investigate the connection between fibre properties and de-coherence of photon state used as information carrier, by developing a QKD test-bed. Namely, tens of kilometres fibre optic link realising a standard platform for validation, quantification and comparison of diverse physical components of a QKD system in a 'real' environment. In particular, together with the studies on de-coherence the test-bed will be used to test photon emitters and photon receivers. In detail, MIQC will:
- Investigate the evolution of the state induced by the propagation in fibre
- Characterise devices used for state preparation and detection
- Realise an optical fibre based QKD test-bed with modular structure so that the different physical components can be interchanged in order to test them in a 'real' environment.
- realise measurement devices for in-line calibration of QKD systems
Photon Receivers
MIQC will provide a measurement framework for the characterisation of photon detectors developed for QKD. The various parameters necessary for a detection technology to be considered a suitable QKD photon detector will be quantified and measured in a traceable manner. In details, MIQC will:
- Establish traceable measurement of detection efficiency to national standards for commercial single-photon detectors operating at 1.55 μm used as QKD quantum receivers
- Provide proper characterisation of relevant properties of for commercial single-photon detectors used in QKD other than detection efficiency
- Develop a primary standard for calibrating photon receivers based on an absolute light source of synchrotron radiation at 1.55 μm
