The main objective of the proposed research program is to build a diamond-based single-photon source that is capable of emitting
entangled strings of photons for resource-efficient photonic quantum computing.
This work will address the main challenge in realizing scalable multi-photon quantum information processing within the framework of
measurement-based quantum computing. We will follow the recent theoretical work to realize a string of single photons that are
entangled as a cluster state – the generic resource for measurement-based quantum computing.
To achieve this ambitious goal we will push current technology far beyond state of the art by obtaining advanced quantum control over
single-photon emitters based on nitrogen-vacancy centres in diamond, that to date have been only used for obtaining individual,
unentangled photons. This will break new ground for the efficient generation of entangled photons, and will make large regions of
previously inaccessible quantum state space available for modern quantum technologies.
We will develop new theory to perform feasible quantum state tomography of the emitted light by using only passive optical elements.
Furthermore we will use new experimental methods for the implementation of quantum gates, combining fast electro-optical switches
and high-efficiency superconducting detectors, to enable adaptive measurements for error correction.
The results of these experiments will be crucial for scalable quantum computing in realistic scenarios and open alternative
perspectives for novel applications using quantum-enhanced information technology.