Figure 2
From: Two-qubit quantum gate and entanglement protected by circulant symmetry
(a) Time evolution of the spin populations. We solve numerically the time-dependent Schrödinger equation with Hamiltonian \( {\hat{H}} (t)={ {\hat{H}} }_{0}+{ {\hat{H}} }_{{\rm{cir}}}^{(2)}\). The parameters are set to J0/2π = 2 kHz, Ω1/2π = 50 kHz, Δ1/2π = 30 kHz, Δ2/2π = 10 kHz, ω/2π = 0.2 kHz, φ = π/4 and gate time \({t}_{\max }=1.25\) ms. (b) Adiabatic transition to the quantum Fourier state \(\left|{\psi }_{3}\right\rangle \) using Hamiltonian (19). The parameters are set to J0/2π = 2.0 kHz, V0/2π = 3.8 kHz, Ω1/2π = 30 kHz, ω/2π = 0.6 kHz, φ = π/4 and gate time \({t}_{\max }\approx 417\ \mu \)s.
