Fig. 1: Time-resolved switching of the nuclear spin state.
From: Single-shot readout of the nuclear spin of an on-surface atom
a Diagram of the measurement scheme: the I = 7/2 nuclear spin (blue) of a 49Ti atom coupled to the S = 1/2 electron spin (brown) via the hyperfine interaction. Only when the nuclear spin is in the mI = −7/2 state, does the applied RF signal at frequency fprobe lead to a tunneling current increase IESR. Right: spin energy diagram in the limit of a strong magnetic field, where the Zeeman splitting dominates and the eigenstates can be approximated by product states. b STM topography (10 pA, 60 mV) of two Ti isotopes on MgO/Ag(100). c ESR frequency sweeps (3.0 pA, 60 mV, Bz = 1.35 T, VRF = 17 mV, averaging time 3 s, lock-in frequency 270 Hz) measured on the two Ti atoms in (b). VRF refers to the zero-to-peak RF voltage amplitude at the tunnel junction. d Section of a time trace of the tunneling current at fixed tip height (60 mV, averaging time 20 ms) with fprobe corresponding to mI = −7/2. The current histogram on the right is fitted with a two-Gaussian distribution (black line).
