  More than ten years ago a first step towards quantum error correction (QEC)
was implemented [Phys. Rev. Lett. 81, 2152 (1998)]. The work showed there was
sufficient control in nuclear magnetic resonance (NMR) to implement QEC, and
demonstrated that the error rate changed from $\epsilon$ to approximatively
$\sim\epsilon^2$. In the current work we reproduce a similar experiment using
control techniques that have been since developed, such as GRAPE pulses. We
show that the fidelity of the QEC gate sequence, and the comparative advantage
of QEC are appreciably improved. This advantage is maintained despite the
errors introduced by the additional operations needed to protect the quantum
states.
