Efficient Decomposition of Unitary Matrices in Quantum Circuit Compilers

Journal Article (2022)
Author(s)

A.M. Krol (TU Delft - Quantum Circuit Architectures and Technology)

A. Sarkar (TU Delft - Computer Engineering)

I. Ashraf (HITEC University)

Zaid Al-Ars (TU Delft - Computer Engineering)

K.L.M. Bertels (Universidade do Porto, Katholieke Universiteit Leuven)

Research Group
Quantum Circuit Architectures and Technology
Copyright
© 2022 A.M. Krol, A. Sarkar, I. Ashraf, Z. Al-Ars, K.L.M. Bertels
DOI related publication
https://doi.org/10.3390/app12020759
More Info
expand_more
Publication Year
2022
Language
English
Copyright
© 2022 A.M. Krol, A. Sarkar, I. Ashraf, Z. Al-Ars, K.L.M. Bertels
Research Group
Quantum Circuit Architectures and Technology
Issue number
2
Volume number
12
Pages (from-to)
1-20
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

Unitary decomposition is a widely used method to map quantum algorithms to an arbitrary set of quantum gates. Efficient implementation of this decomposition allows for the translation of bigger unitary gates into elementary quantum operations, which is key to executing these algorithms on existing quantum computers. The decomposition can be used as an aggressive optimization method for the whole circuit, as well as to test part of an algorithm on a quantum accelerator. For the selection and implementation of the decomposition algorithm, perfect qubits are assumed. We base our decomposition technique on Quantum Shannon Decomposition, which generates O(344n) controlled-not gates for an n-qubit input gate. In addition, we implement optimizations to take advantage of the potential underlying structure in the input or intermediate matrices, as well as to minimize the execution time of the decomposition. Comparing our implementation to Qubiter and the UniversalQCompiler (UQC), we show that our implementation generates circuits that are much shorter than those of Qubiter and not much longer than the UQC. At the same time, it is also up to 10 times as fast as Qubiter and about 500 times as fast as the UQC.