Fig. 2: Employed sensing scheme.
From: Amplitude and frequency sensing of microwave fields with a superconducting transmon qudit
First, the shift of the first qudit transition Δ1 is determined from the frequency of the corresponding Ramsey oscillations. Second, Δ1 is used to adjust the resonant π-pulse which excites the qudit to the \(\left|1\right\rangle\) state. Then, an additional Ramsey experiment is performed between \(\left|1\right\rangle\) and \(\left|2\right\rangle\) measuring Δ2. Third, Δ1 and Δ2 are processed by a pair of lookup tables to determine the frequency and amplitude of the microwave field causing the shifts. Here, only the lookup table for Δ1 is shown. The sensor limits depicted within the lookup table are derived in the main section.
