Fig. 2: Resetting the target qubit after a free evolution.
From: Verification of a resetting protocol for an uncontrolled superconducting qubit
On the Bloch spheres, the evolution of the states for the three phases are presented: After state preparation (a, e, i), after free evolution (b, f, j), and after resetting (c, g, k). The resetting protocol is applied when the free-evolution induced phase is φ = 3π/8. The red dots mark the state before and after a successful reset. The blue dots mark a free evolution without resetting as a comparison, simulating the results of the time-independent Hamiltonian \({{\mathcal{H}}}_{0}\). As the resetting protocol requires three more free evolutions, the state without the resetting process is measured till φ = 3π/2. From top to bottom, each row shows a different version of the resetting protocol in case 1, demonstrated the resetting process for a superposition state \(\left|-\right\rangle\), a classical state \(\left|1\right\rangle\), and a mixed state, respectively. In (d, h, l), the trace distance after the application of resetting protocol are observed jumping from 0.557, 0.564, and 0.506, to 0.214, 0.277, and 0.246, respectively.
