Fig. 3. Dynamical signatures of topological edge states and the topological charge pump.

a1–a3 Time evolution of the excitation probability P_j with $b=\frac{1}{3}$, Δ/2π = 12 MHz and ϕ = 2π/3 after initially exciting the leftmost qubit Q₁ (a1), the central qubit Q₈ (a2), and the rightmost qubit Q₁₅ (a3). b1–b3, Experimental data of the squared FT magnitudes ∣A₁∣², ∣A₈∣², and ∣A₁₅∣², when choosing Q₁ (b1), Q₈ (b2), and Q₁₅ (b3) as the target qubits. c1–c3, Time evolution of an excitation initially prepared at the central qubit Q₈ when it is forward pumped (c1), not pumped (c2) and backward pumped (c3), respectively, with Δ/2π = 36 MHz for an initial ϕ₀ = 5π/3. d Displacement of the centre of mass (CoM) δx versus time t in one pumping cycle with period T for the cases in (c1–c3). The error bars are 1 SD, calculated from all 10 groups of experimental results.