In a semiconductor spin qubit with sizable spin-orbit coupling, coherent spin rotations can be driven by a resonant gate-voltage modulation. Recently, we have exploited this opportunity in the experimental demonstration of a hole spin qubit in a silicon device. Here we investigate the underlying physical mechanisms by measuring the full angular dependence of the Rabi frequency as well as the gate-voltage dependence and anisotropy of the hole g-factors. We show that a g-matrix formalism can simultaneously capture and discriminate the contributions of two mechanisms so far independently discussed in the literature: one associated with the modulation of the g factors, and measurable by Zeeman energy spectroscopy, the other not. Our approach has a general validity and can be applied to the analysis of other types of spin-orbit qubits.
@article{arxiv.1710.08690,
title = {Electrical spin driving by $g$-matrix modulation in spin-orbit qubits},
author = {Alessandro Crippa and Romain Maurand and Léo Bourdet and Dharmraj Kotekar-Patil and Anthony Amisse and Xavier Jehl and Marc Sanquer and Romain Laviéville and Heorhii Bohuslavskyi and Louis Hutin and Sylvain Barraud and Maud Vinet and Yann-Michel Niquet and Silvano De Franceschi},
journal= {arXiv preprint arXiv:1710.08690},
year = {2018}
}
Comments
Letter format (4 pages, 4 figures). Detailed theory in Supplemenatl Material