Dennis Willsch

TL;DR: The performance of the quantum approximate optimization algorithm is evaluated by using three different measures: the probability of finding the ground state, the energy expectation value, and a ratio closely related to the approximation ratio as mentioned in this paper.

TL;DR: A number of simple quantum circuits are explored as benchmarks for gate-based quantum computing devices and it is shown that circuits performing identity operations are very simple, scalable and sensitive to gate errors and are therefore very well suited for this task.

TL;DR: In this paper, the success of implementing superconducting qubit-based quantum gates is analyzed by numerically solving time-dependent Schrodinger equations for a transmon system and it is found that such metrics are not reliable to predict the performance of a quantum algorithm when the gates are used repeatedly.

TL;DR: In this paper, the mathematical foundations of numerical simulation methods that are based on the use of random states are reviewed and extended, in a self-contained way, and the power and versatility of this simulation method are discussed.

TL;DR: A simulator for quantum computers composed of superconducting transmon qubits is developed and a protocol from the theory of quantum error correction and fault tolerance is tested that systematically improves the performance of transmon quantum computers in the presence of characteristic control and measurement errors.