Pauli spin blockade for holes in a hot silicon FinFET*

Quantum information can be encoded in the spin state of a single electron or hole confined to a semiconductor quantum dot (QD) (Loss and DiVincenzo, PRA57, 120 (1998)). Silicon is a particularly promising platform for scalable spin-based quantum computing due to its fully developed, industrial manufacturing processes. Furthermore, a nearly nuclear-spin-free environment can be engineered by means of isotopic purification. Holes in silicon are of particular interest, since they are subject to a strong spin-orbit-interaction, allowing for fast, all-electrical spin manipulation (Maurand et al., Nature Comm. 7, 13575 (2016)).
We define single and double QDs in a FinFET-like device architecture. A second gate layer, which is fabricated in a self-aligned process, allows for in-situ adjustments of the tunnel couplings and makes these devices highly tunable. In addition, conventional impurity-doped source and drain contacts are replaced in an overlapping-gate structure by a metallic silicide. We observe Coulomb blockade and, furthermore, Pauli spin blockade for both electrons and holes. The large singlet-triplet splitting allows spin blockade for holes to be observed at temperatures as high as 10 K, paving the way for a hot spin-qubit.