  Modular quantum computing architectures offer a promising alternative to
monolithic designs for overcoming the scaling limitations of current quantum
computers. To achieve scalability beyond small prototypes, quantum
architectures are expected to adopt a modular approach, featuring clusters of
tightly connected quantum bits with sparser connections between these clusters.
Efficiently distributing qubits across multiple processing cores is critical
for improving quantum computing systems' performance and scalability. To
address this challenge, we propose the Hungarian Qubit Assignment (HQA)
algorithm, which leverages the Hungarian algorithm to improve qubit-to-core
assignment. The HQA algorithm considers the interactions between qubits over
the entire circuit, enabling fine-grained partitioning and enhanced qubit
utilization. We compare the HQA algorithm with state-of-the-art alternatives
through comprehensive experiments using both real-world quantum algorithms and
random quantum circuits. The results demonstrate the superiority of our
proposed approach, outperforming existing methods, with an average improvement
of 1.28$\times$.
