Fig. 1: Creation of a fluorescent molecular STM probe.

a Conductance G as a function of tip-substrate distance z recorded during the PTCDA attachment procedure in units of the conductance quantum G₀. The tip is approached towards the molecule with V = 20 mV (green dotted line, (1)) until a contact forms, indicated by the sudden increase of conductance (green arrow). Upon retracting the tip, the molecule is first cleaved from the substrate (green solid line, (2)) and finally, at 2.1 nm completely detached from the substrate ((3), loss of substrate-molecule contact indicated by the black vertical line). At 2.15 nm, the bias voltage is increased from 20 mV to 2.5 V. The inset is an STM constant current image (I = 30 pA, V = −300 mV, scale bar is 1 nm) of the molecule before lifting, as well as its Lewis structure. The position where the tip is approached is indicated by a green cross. b STML spectra of a metallic (black) and a PTCDA tip (red) in front of a bare Ag(111) surface. The peak at  ≈1.34 eV is associated to the trion fluorescence (X⁻) of the suspended PTCDA. X⁻ acquisition parameters: V = 2.5 V, I = 70 pA, \(t=6\,\min\). Plasmon acquisition parameters: V = 2.5 V, I = 50 pA, \(t=2\,\min\). Source data are provided as a Source Data file.