Fig. 4: Long-range coherence of the YSR quantum projection.
From: Non-local detection of coherent Yu–Shiba–Rusinov quantum projections
a,b, Constant-current STM images of a Ag corral (Lx = 22.26 nm, Ly = 9.1 nm) with the Fe atom placed in the topmost quarter (a) and of the same corral in which the Fe atom was replaced with a Ag atom (b) (Fourier filtered, Vbias = −5 mV, Iset = 1 nA). c,d, Constant-height dI/dV maps taken close to −Eβ inside the corrals of a (c) and b (d) (Vbias = −1.67 mV, Vstab = −5 mV, Istab = 1 nA, \({V}_{{\rm{mod}}}=100\,\upmu {\rm{V}}\)). e,f, dI/dV line profiles taken along the longitudinal vertical axes through the corrals in a (e) and b (f) (Vstab = −5 mV, Istab = 1 nA, \({V}_{{\rm{mod}}}=50\,\upmu {\rm{V}}\)). The red and blue arrows above e indicate Vbias corresponding to −Eβ and +Eβ, respectively. The grey vertical lines indicate the bias voltage of the tip gap Δt/e. a.u.: output voltage (in volts) of the lock-in amplifier using the same lock-in parameters for c–f.
