Extended Data Fig. 2 | Pulse cycles used for the transport measurements.
a Pulse cycles used for the randomized benchmarking experiments. The
measurement pulse cycle consists of m gates randomly drawn from the Clifford
group Crand and a final Clifford gate projecting the qubit onto the spin-up state.
The reference pulse cycle consists of the same m Clifford gates and a different
final Clifford gate projecting the qubit onto the spin-down state. Each cycle is
repeated N times, and a series of typically k = 50 independent randomly drawn
measurement and reference pulse cycles are alternated. These k = 50 different
draws are thus hardware-averaged on the lock-in amplifier, and the entire
experiment is repeated and averaged 30 times, yielding a total approximate 10^5
repetitions of 1, 500 different randomly drawn Clifford sequences of length m.
An example of the qubit evolution for each pulse cycle is plotted on the Bloch
sphere below. b, Pulse cycles used for the exchange mapping experiments. The
measurement pulse cycle consists of a broad preparation and restoring pulse
at frequency f 3 (f 1 ), around a probing pulse at frequency fprb. The reference
pulse cycle consists solely of the probing pulse at fprb. The qubit evolutions for
the different resonance conditions are plotted on the Bloch sphere and
illustrate the different signals measured in Fig. 4c, d.