Fig. 1: Design for a Ge hole quantum dot.
From: Effect of disorder and strain on the operation of planar Ge hole spin qubits
a With realistic gatestack, b cross-section of the design showing the 10 nm thick Ge layer between the lower and upper Ge/Si0.2Ge0.8 layers of thickness 60 nm and 10 nm, respectively. The first layer of Al source and drain gates (20 nm thick) sits atop the heterostructure, followed by a dielectric Al2O3 layer (17 nm), and a second layer of Pd/Ti electrodes (5/35 nm). The hole quantum dot forms directly under the Pd/Ti top gate(TG), as indicated by the oval shape in the Ge layer in (b). The angular orientations of the applied in-plane magnetic field B and the ac electric field \({\tilde{E}}_{{\rm{ac}}}\) with respect to the [100] crystallographic axis are denoted by θ and ϕ, respectively.
