QUDA: quantum distributed adder algorithm

While adders are required for many classical and quantum algorithms, nowadays’ single quantum computer implementations cannot handle the large qubit counts required in practical applications. Implementing a distributed approach is currently the only solution, but it poses the challenge of communication latency. This paper introduces a quantum distributed adder algorithm (QUDA) as a solution for many applications that require large qubit counts. QUDA offers a logarithmic number of instances of quantum data transfer for the addition of two numbers in comparison with existing solutions which are generally either based on ripple carry adders with a linear number of transmission rounds or attempt to distribute an existing monolithic circuit without specializing their techniques to adders. We include implementation details and the used testing methodology, showcasing the correctness and efficiency of the proposed algorithm.