A non-anyonic qudit ZW-calculus

TL;DR

This paper introduces a simplified non-anyonic qudit ZW-calculus with easier interpretation and establishes its universality for pure qudit quantum computing, improving computational simplicity over previous models.

Contribution

It presents a new qudit ZW-calculus with simpler generators and rewriting rules, aligning with the qubit ZW-calculus and enabling universal pure qudit quantum computing.

Findings

Simplified W spider with linear map interpretation

Established translation between qudit ZW and ZX-calculus

Proved universality for pure qudit quantum computing

Abstract

ZW-calculus is a useful graphical language for pure qubit quantum computing. It is via the translation of the completeness of ZW-calculus that the first proof of completeness of ZX-calculus was obtained. A d-level generalisation of qubit ZW-calculus (anyonic qudit ZW-calculus) has been given in [Hadzihasanovic 2017] which is universal for pure qudit quantum computing. However, the interpretation of the W spider in this type of ZW-calculus has so-called q-binomial coefficients involved, thus makes computation quite complicated. In this paper, we give a new type of qudit ZW-calculus which has generators and rewriting rules similar to that of the qubit ZW-calculus. Especially, the Z spider is exactly the same as that of the qudit ZX-calculus as given in [Wang 2021], and the new W spider has much simpler interpretation as a linear map. Furthermore, we establish a translation between this qudit ZW-calculus and the qudit ZX-calculus which is universal as shown in [Wang 2021], therefore this qudit ZW-calculus is also universal for pure qudit quantum computing.