Geometric Aspects of Composite Pulses
Abstract
Unitary operations acting on a quantum system must be robust against systematic errors in control parameters for reliable quantum computing. Composite pulse technique in nuclear magnetic resonance (NMR) realises such a robust operation by employing a sequence of possibly poor quality pulses. In this article, we demonstrate that two kinds of composite pulses, one compensates for a pulse length error in a one-qubit system and the other compensates for a J-coupling error in a twoqubit system, have vanishing dynamical phase and thereby can be seen as geometric quantum gates, which implement unitary gates by the holonomy associated with dynamics of cyclic vectors defined in the text.
Cite
@article{arxiv.1204.2437,
title = {Geometric Aspects of Composite Pulses},
author = {Tsubasa Ichikawa and Masamitsu Bando and Yasushi Kondo and Mikio Nakahara},
journal= {arXiv preprint arXiv:1204.2437},
year = {2012}
}
Comments
20 pages, 4 figures. Accepted for publication in Philosophical Transactions of the Royal Society A