Measuring entanglement in quantum magnetic systems with strong long-range correlations
D-Wave systems purports to have designed a quantum processor based on scalable architecture that physically implements quantum annealing, an algorithm that can be used to solve a wide variety of optimization problems. In order for D-Wave devices to exhibit a performance advantage over classical processors, it is necessary that the devices utilize a resource that is inaccessible to any classical algorithm. This resource is generally associated with quantum entanglement. Establishing entanglement in devices operating a large number of quantum bits with strong long-range correlations would be an important milestone in the development of scalable quantum computing architectures. In this project, we will develop measures for quantifying entanglement in such systems, calculate them numerically in simulations of the D-Wave devices, and propose an experimental method that can be used to establish entanglement in the corresponding physical devices. We will then compare the performance of quantum annealing on a D-Wave device to classical algorithms on a classical processor, using a variety of different classes of optimization problems as benchmarks.