Fig. 5: Hole qubit properties with full strain profile.
From: Effect of disorder and strain on the operation of planar Ge hole spin qubits
For a circular dot of radius ad = 45 nm, a the qubit g-factor is anisotropic and exhibits a large ~π/4 rotation of the principal axes. For all subfigures a–e, the top and bottom panels signify results for Fz = 1.5 MV/m and Fz = 15 MV/m, respectively. b At ∣B∣ = 670 mT, fast EDSR is predicted with gate time ~10 ns, and a similar fπ(θ, ϕ) trend to the tight binding calculation is observed. Here, ∣Eac∣ = 10 kV/m. c The ∝ ∣B∣2 variation of the hole qubit dephasing rate (\({({T}_{2,RTN}^{* })}^{-1}\)) due to the random telegraph noise from a single charge defect, with uniaxial strain (red) and inhomogeneous strain (green). The single charge defect is assumed to be situated at \((50\sqrt{2},50\sqrt{2},0)\). d The linear variation of the EDSR Rabi frequency fπ w.r.t. the magnetic field strength ∣B∣. In the presence of strain inhomogeneity (denoted by “ih” on the green axes), fπ is ~100× higher than the uniaxial strain scenario (red). e Relaxation rate (Γ1) as a function of magnetic field strength.
