English

The Universality of the Quantum Fourier Transform in Forming the Basis of Quantum Computing Algorithms

Quantum Physics 2007-05-23 v1

Abstract

The quantum Fourier transform (QFT) is a powerful tool in quantum computing. The main ingredients of QFT are formed by the Walsh-Hadamard transform H and phase shifts P(.), both of which are 2x2 unitary matrices as operators on the two-dimensional 1-qubit space. In this paper, we show that H and P(.) suffice to generate the unitary group U(2) and, consequently, through controlled-U operations and their concatenations, the entire unitary group U(2^n) on n-qubits can be generated. Since any quantum computing algorithm in an n-qubit quantum computer is based on operations by matrices in U(2^n), in this sense we have the universality of the QFT.

Keywords

Cite

@article{arxiv.quant-ph/0007122,
  title  = {The Universality of the Quantum Fourier Transform in Forming the Basis of Quantum Computing Algorithms},
  author = {Charles M. Bowden and Goong Chen and Zijian Diao and Andreas Klappenecker},
  journal= {arXiv preprint arXiv:quant-ph/0007122},
  year   = {2007}
}

Comments

12 pages, 3 figures, submitted to SIAM Journal on Computing