During my MS by Research at the Centre for Quantum Science and Technology, IIIT Hyderabad, I studied how three parties sharing entanglement can split and rebuild a quantum secret, and what that reveals about teleportation and Bell nonlocality.
In quantum secret sharing, a dealer distributes a quantum state so that a reconstructor can recover it only with help from an assistant. This paper asks which pure three-qubit states make the best resources for that task, given limits on how well each dealer–receiver channel could be used for teleportation.
For a fixed maximum teleportation fidelity across the dealer's two channels, we characterized the states that reach the highest possible reconstruction fidelity, and gave them a single-parameter canonical form (MSR states).
Similarly, for a fixed maximum Bell-CHSH value across the dealer–reconstructor and dealer–assistant channels, we found the best reconstruction fidelity that can be achieved.
Every secret-shareable state satisfies Bell's inequality in both dealer partitions. So pure three-qubit states whose bipartite channels violate Bell's inequality are not suitable resources for secret sharing.
Builds on the paper above to identify the best candidate resource states for quantum secret sharing, setting a practical limit on information transfer in a resource-theoretic view of secret sharing.
I'm open to research-engineering roles and collaborations where formal depth meets production systems.