Dephasing-tolerant quantum sensing for transverse magnetic fields with spin qudits

We propose a dephasing-tolerant protocol for quantum sensing of transverse magnetic fields which exploits spin qudit sensors with embedded fault-tolerant (FT) quantum error correction. By exploiting longitudinal drives, the transverse field induces logical Rabi oscillations between encoded states, whose frequency is linear in the transverse field to be probed. Numerical simulations show that the present FT protocol enables the detection of very small fields, orders of magnitudes below the limit imposed by the coherence time.