QLunch: A quantum code for quantum homomorphic encryption and malleable quantum shared secrets

Speaker: Si-Hui Tan from Singapore University of Technology and Design and Visiting Guest Researcher at NBIA.

Title: 
A quantum code for quantum homomorphic encryption and malleable quantum shared secrets

Abstract: 
In today’s computing landscape, the adopted infrastructure is one of distributed networks in which computational tasks can be delegated to remote computers, and information can be shared among multiple nodes. Protocols are needed to protect the security of the data during computation, even when the computation is done in a distributed manner. Homomorphic encryption and function evaluations of shared secrets are two such protocols. We expect that their quantum analogues will be similarly useful when quantum computers become accessible online. I will present a quantum code that allows the evaluation of Clifford- and T-gate evaluations on encrypted quantum data, and on quantum shared secrets. These properties form the basis for quantum analogues of homomorphic encryption and function evaluations of shared secrets respectively. The gates are performed transversally on qubits that form a logical qubit, but special provisions have to be made for the T-gates in order to provide the security in these protocols. This highlights the use of quantum codes for secure delegated quantum computations and paves a way forward for creating more protocols.

Bio:
Si-Hui Tan is a Research Scientist at the Singapore University of Technology and Design, and a visiting Guest Researcher at NBIA. She completed her PhD in Physics at MIT in 2010, and was a scientist at the Data Storage Institute in Singapore previously.

Si-Hui’s research interests lie in quantum information science, which is at the intersection of quantum mechanics and information theory. Currently, she is focused on creating cryptographic primitives for secure delegated quantum computing, in which information can be processed by a server without the server learning about that information. Si-Hui is also interested in finding new ways of processing information in quantum optical systems, and exploring the potential of these systems in various applications.