DisQ: A Model of Distributed Quantum Processors (Extended Version)
This work addresses the lack of formal models for distributed quantum computing, providing a foundational tool for verifying distributed quantum programs.
DisQ introduces the first formal model for distributed quantum processors, enabling analysis of distributed quantum programs. It provides a language combining CHAM and MDP to distinguish concurrent and distributed behaviors, and a simulation relation to verify equivalence between sequential and distributed quantum algorithms.
The next generation of distributed quantum processors combines single-location quantum computing and quantum networking techniques to permit large entangled qubit groups to be established through remote processors, and quantum algorithms can be executed distributively. We present DisQ, as the first formal model of distributed quantum processors, and permit the analysis of distributed quantum programs in the new computation environment. The core of DisQ is a distributed quantum programming language that combines the concepts of Chemical Abstract Machine (CHAM) and Markov Decision Processes (MDP) with the objective of providing clearly distinguishing quantum concurrent and distributed behaviors. Based on the DisQ language, we develop a simulation relation, based on classical simulation infrastructure, to check the equivalence of a quantum algorithm and its distributed versions so that users can develop the distributed version of a sequential quantum program via a simulation check.