Oak Ridge National Laboratory Knoxville, United States of America
Numerical simulation of large quantum circuits is an indispensable tool for validating near-term quantum devices as well as studying quantum algorithms. The emergence of Exascale HPC systems presents new opportunities for pushing the boundaries of quantum simulation. We present a modernized version of our tensor network quantum virtual machine (TNQVM) quantum circuit simulator which serves as a virtual accelerator in the eXtreme-scale ACCelerator (XACC) framework. The modernized TNQVM is based on the general propose tensor network processing library, ExaTN. We have implemented multiple configurable quantum circuit simulators catering to either exact quantum circuit simulation, via the full tensor network contraction, or approximate quantum state representations, via suitable tensor factorizations. For the latter case, we also implement the locally purified matrix product operator formalism which simulates quantum circuits subject to stochastic noise. By combining the portable XACC quantum programming frontend and the scalable ExaTN numerical backend we introduce an end-to-end virtual quantum development environment which can scale from laptops to future Exascale platforms. We report initial benchmarks of our simulation framework which includes a demonstration of distributed execution, incorporation of the quantum decoherence models, and application to the seminal Sycamore quantum supremacy circuits.