AQUA: Hardware-Agnostic Qubit Allocation for Quantum Multi-Programming

Quantum multi-programming, which is a method to run multiple quantum programs concurrently, has the potential to significantly improve the overall throughput and resource utilization. However, previous approaches do not always guarantee consistent performance (e.g., circuit complexity and reliability) over all possible hardware platforms due to qubit connectivity and qubit error rates in individual hardware platforms. This paper proposes hardware-Agnostic QUbit Allocation, named $A Q U A$, that allows multiple quantum programs to run simultaneously while ensuring high reliability regardless of hardware platforms. The proposed AQUA optimizes quantum programs at the logicallevel, without physical qubit mappings and allocations, to ensure that they consist of fewer gates and shorter depths. By attempting to optimize quantum programs at the logical-level, regardless of hardware connectivity, the AQUA can ensure consistent circuit complexity and reliability. Then, the AQUA dynamically allocates quantum programs to more reliable physical qubits depending on circuit depths and qubit error rates. The effectiveness of the AQUA is demonstrated using several quantum hardware platforms, showing that AQUA ensures high reliability and consistent circuit complexity.