Developing a Grover's quantum algorithm emulator on standalone FPGAs: optimization and implementation

Quantum computing (QC) leverages superposition, entanglement, and parallelism to solve complex problems that are challenging for classical computing methods. The immense potential of QC has spurred explosive interest and research in both academia and industry. However, the practicality of QC based on large-scale quantum computers remains limited by issues of scalability and error correction. To bridge this gap, QC emulators utilizing classical computing resources have emerged, with modern implementations employing FPGAs for efficiency. Nevertheless, FPGA-based QC emulators face significant limitations, particularly in standalone implementations required for low-power, low-performance devices like IoT end nodes, embedded systems, and wearable devices, due to their substantial resource demands. This paper proposes optimization techniques to reduce resource requirements and enable standalone FPGA implementations of QC emulators. We specifically focused on Grover's algorithm, known for its excellent performance in searching unstructured databases. The proposed resource-saving optimization techniques allow for the emulation of the largest possible Grover's algorithm within the constrained resources of FPGAs. Using these optimization techniques, we developed a hardware accelerator for Grover's algorithm and integrated it with a RISC-V processor architecture. We completed a standalone Grover's algorithm-specific emulator operating on FPGAs, demonstrating significant performance enhancements and resource savings afforded by the proposed techniques.