Clifford Gate Optimisation and T Gate Scheduling: Using Queueing Models for Topological Assemblies

Alexandru Paler; Robert Basmadjian

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arXiv · 1906.06400

Clifford Gate Optimisation and T Gate Scheduling: Using Queueing Models for Topological Assemblies

Alexandru Paler·Robert Basmadjian

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Abstract

Clifford gates play a role in the optimisation of Clifford+T circuits. Reducing the count and the depth of Clifford gates, as well as the optimal scheduling of T gates, influence the hardware and the time costs of executing quantum circuits. This work focuses on circuits protected by the surface quantum error-correcting code. The result of compiling a quantum circuit for the surface code is called a topological assembly. We use queuing theory to model a part of the compiled assemblies, evaluate the models, and make the empiric observation that at least for certain Clifford+T circuits (e.g. adders), the assembly's execution time does not increase when the available hardware is restricted. This is an interesting property, because it shows that T gate scheduling and Clifford gate optimisation have the potential to save both hardware and execution time.

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Alexandru Paler, Robert Basmadjian. 2019-06-14. Clifford Gate Optimisation and T Gate Scheduling: Using Queueing Models for Topological Assemblies. https://arxiv.org/abs/1906.06400

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