Quantum Benchmarking: entanglement measures in quantum computers

Abstract

Quantum computation has emerged as a promising paradigm shift in the field of computing, and with the advent of new quantum computers, it has become crucial to assess and quantify their performance. Benchmarking, a wellestablished practice in the field, plays a vital role in this regard. One effective way to evaluate a quantum computer’s capabilities is by measuring the amount of entanglement it exhibits, as entanglement is a fundamental characteristic of quantum systems. In this thesis, we provide a comprehensive overview of the current landscape of quantum benchmarking and propose several protocols for estimating the Rényi entropy of quantum states, which offers valuable insights into the entanglement structure of these states. We present a protocol based on the renowned Swap test, specifically designed for future fault-tolerant devices, as well as another protocol based on randomized measurements to address the limitations of current NISQ devices. We have implemented these protocols on the quantum simulation framework of Qibo, ensuring an efficient and reliable execution on any quantum computer, in particular the one at the Barcelona Supercomputing Center (BSC). Through this work, we aim to contribute to the advancement of quantum benchmarking and facilitate the assessment of entanglement in quantum computing systems.