|Title||Entanglement bounds on the performance of quantum computing architectures|
|Publication Type||Journal Article|
|Year of Publication||2020|
|Authors||Z. Eldredge, L. Zhou, A. Bapat, J. R. Garrison, A. Deshpande, F. T. Chong, and|
|Journal||Phys. Rev. Res.|
There are many possible architectures of qubit connectivity that designers of future quantum computers will need to choose between. However, the process of evaluating a particular connectivity graph's performance as a quantum architecture can be difficult. In this paper, we show that a quantity known as the isoperimetric number establishes a lower bound on the time required to create highly entangled states. This metric we propose counts resources based on the use of two-qubit unitary operations, while allowing for arbitrarily fast measurements and classical feedback. We use this metric to evaluate the hierarchical architecture proposed by A. Bapat et al. [Phys. Rev. A 98, 062328 (2018)] and find it to be a promising alternative to the conventional grid architecture. We also show that the lower bound that this metric places on the creation time of highly entangled states can be saturated with a constructive protocol, up to a factor logarithmic in the number of qubits.