Article
7LPH KRXUV I 0+]
&RXQWVI 0+] Q1Q2Extended Data Fig. 5 | Temporal dependence of the resonance frequency.
We track the resonance frequency of both Q1 and Q2 over the time of
approximately 110 h. We observe that the qubit frequency remains remarkably
stable over this period, but do observe discrete, uncorrelated steps in the
resonance frequencies of both qubits. The resonance frequency of Q1 only
shows steps of Δf ≈ 2 MHz between two distinct levels, whereas for Q2 we
observe steps of both Δf ≈ 1 MHz and Δf ≈ 2 MHz, between three different levels,
as also becomes apparent from the histogram. The origin of these steps could
be, for example, the slow loading and unloading of charge traps, which
manipulates the qubit resonance frequency through the change in electric
field, or hyperfine coupling to a nearby nuclear spin^36.