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arXiv · 2111.05130

Dynamics of hole singlet triplet qubits with large g-factor differences

Daniel Jirovec·Philipp M. Mutter·Andrea Hofmann·Josip Kukucka·Alessandro Crippa·Frederico Martins·Andrea Ballabio·Daniel Chrastina·Giovanni Isella·Guido Burkard·Georgios Katsaros
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Abstract

The spin-orbit interaction is the key element for electrically tunable spin qubits. Here we probe the effect of cubic Rashba spin-orbit interaction on mixing of the spin states by investigating singlet-triplet oscillations in a planar Ge hole double quantum dot. By varying the magnetic field direction we find an intriguing transformation of the funnel into a butterfly-shaped pattern. Landau-Zener sweeps disentangle the Zeeman mixing effect from the spin-orbit induced coupling and show that large singlet-triplet avoided crossings do not imply a strong spin-orbit interaction. Our work emphasizes the need for a complete knowledge of the energy landscape when working with hole spin qubits.

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Daniel Jirovec, Philipp M. Mutter, Andrea Hofmann, Josip Kukucka, Alessandro Crippa, Frederico Martins, Andrea Ballabio, Daniel Chrastina, Giovanni Isella, Guido Burkard, Georgios Katsaros. 2021-11-09. Dynamics of hole singlet triplet qubits with large g-factor differences. https://doi.org/10.1103/physrevlett.128.126803

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