Dynamics of Hole Singlet-Triplet Qubits with Large <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>g</mml:mi></mml:mrow></mml:math>-Factor Differences
Daniel Jirovec, Philipp M. Mutter, Andrea Hofmann, Alessandro Crippa, Marek Rychetsky, David L. Craig, Josip Kukucka, Frederico Martins, Andrea Ballabio, Natalia Ares, Daniel Chrastina, Giovanni Isella, Guido Burkard, Georgios Katsaros
Abstract
The spin-orbit interaction permits to control the state of a spin qubit via electric fields. For holes it is particularly strong, allowing for fast all electrical qubit manipulation, and yet an in-depth understanding of this interaction in hole systems is missing. Here we investigate, experimentally and theoretically, the effect of the cubic Rashba spin-orbit interaction on the mixing of the spin states by studying singlet-triplet oscillations in a planar Ge hole double quantum dot. Landau-Zener sweeps at different magnetic field directions allow us to disentangle the effects of the spin-orbit induced spin-flip term from those caused by strongly site-dependent and anisotropic quantum dot g tensors. Our work, therefore, provides new insights into the hole spin-orbit interaction, necessary for optimizing future qubit experiments.