A Scalable High-Precision and High-Throughput Architecture for Emulation of Quantum Algorithms

Quantum hardware emulators using field programmable gate arrays (FPGAs) have been demonstrated to efficiently exploit the inherent parallelism of quantum algorithms and perform better than sequential software simulators. However, one key problem in mapping quantum circuits on FPGAs is the exponential increase in resource requirements with the increase in the number of quantum bits (qubits). As a result, the precision of hardware emulators is often reduced to save resources and accommodate larger quantum circuits which results in lower accuracy and lower throughput. In this paper, we present a full precision FPGA quantum emulator that uses 32-bit floating-point arithmetic and has a fully pipelined architecture. Our emulator is capable of emulating an entangled 4-qubit quantum system performing Quantum Fourier Transform, Grover's Search algorithms on a single FPGA node. Our experimental work was conducted on a highly scalable multi-node (multi-FPGA) state-of-the-art high-performance reconfigurable computer (HPRC). Experimental results show that our emulator is functionally accurate and has a higher operating frequency relative to other emulators. For emulating larger-scale circuits we propose using a multi-node architecture scheme with low latency, high bandwidth inter-node communication.