Anthony Laing

We design and fabricate a quantum photonic circuit to generate a 4-qubit state to load single qubit information and implement a quantum error correction code to demonstrate its capability of detecting and correcting a single-bit error. The encoded quantum information can be reconstructed from different types of errors and achieve an average state fidelity of 86%. We further extend the scheme to demonstrate fault-tolerant measurement-based quantum computing that allows us to redo the qubit operation against the failure of the teleportation process.

As computing becomes more mobile, cashless as well as cardless payment solutions are introduced and a need arises for incorporating QKD in a mobile device. Handheld devices present a particular challenge as the orientation and the phase of a qubit will depend on device motion. This problem is addressed by the reference frame independent (RFI) QKD scheme, providing a protocol to overcome issues with calibration and slow variations in reference frames between the two communicating parties. This indicates that the real world imperfections and the impracticality of calibrating mobile devices can be mitigated to allow the adoption of integrated quantum technologies in portable systems.