Large spin-orbit coupling for holes in Ge/Si nanostructures allows for ultrafast electrical manipulation of spins in quantum dots . However, the large coupling also limits coherence due to charge noise. The ability to tune the strength of the spin-orbit interaction over a large range via gate voltages therefore promises a switch between fast operations and an idling state that is less sensitive to charge noise. Obtaining and tuning such a large spin-orbit coupling requires strong confinement in two dimensions . While this has been demonstrated in Ge nanowires, it has yet to be achieved in lateral quantum dots in Ge/SiGe heterostructures. By doing that one could take advantage of this clean 2D platform that is also promising for scaling up .
We aim to demonstrate this control over the spin-orbit coupling in a strained germanium quantum well by designing and fabricating a gate layout that allows for precise control of the dot shape.
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