Bachelor's thesis presentation. Julian is advised by Philipp Seitz, and Prof. Dr. Christian Mendl.
Previous talks at the SCCS Colloquium
Julian Wagner: Benchmarking Variational Algorithms on Heterogeneous Hardware
SCCS Colloquium |
Modern Noisy Intermediate-Scale Quantum (NISQ) devices of today still suffer from limitations in terms of quantum bit numbers. Despite the fact that those devices are improving and becoming larger in available qubits over time, it remains challenging to secure access to individual devices. Most quantum circuits are smaller than the device’s capabilities, therefore it is crucial to find strategies to take full advantage of today’s limited Noisy Intermediate-Scale Quantum devices. To make use of available quantum resources more efficiently, achieve more effective scaling, and follow the paradigm of distributed quantum computing (DQC), the concept of circuit cutting is evaluated as a possible solution. This thesis investigates the Qiskit circuit cutting addon as a strategy to reduce overall circuit width, focusing on the performance and most importantly the accuracy within the context of Variational Quantum Algorithms (VQAs). The work concentrates on integrating the Qiskit addon into a standard Variational Quantum Eigensolver (VQE) and to approximate the ground state energy of several molecules. For benchmarking purposes, numerous different experiments were conducted to evaluate the effect of different types of ansätze and varying layer configurations on accuracy of the VQE algorithm. The results indicate promising outcomes for the use of circuit cutting in the context of VQE compared to the classical VQE algorithm. Work in the future may involve conducting more tests on heterogeneous quantum hardware.