Extended Data Fig. 7: Spatially averaged dI/dV spectra of the 1 QL Bi2Te3/6 UC FeTe bilayer.
From: Moiré engineering of Cooper-pair density modulation states
a, Spatially averaged dI/dV spectrum from spectroscopic imaging-STM measurements using a PtIr tip (Vs = 8 mV, Is = 1 nA, and Ve = 0.2 mV) in Fig. S8. The average dI/dV spectra remove contributions of QPI and the moiré pattern, revealing two pairs of coherence peaks. Inset: Dynes model fit of the dI/dV spectrum. The black curve shows the symmetrized spectrum, and the red curve shows the fit, yielding Δ1 ~ 1.96 meV and Δ2 ~ 3.32 meV. b, Spatially averaged dI/dV spectrum over a 170 × 170 grid in a 30 × 30 nm2 area from spectroscopic imaging-STM measurements using a superconducting Nb tip (Vs = 10 mV, Is = 1 nA, and Ve = 0.2 mV). c, dI/dV spectrum in (b) after numerically deconvolving the Nb tip contribution. The positions of the coherence peaks match those in (a) measured by a PtIr tip. d, Differential conductance map measured at convoluted coherence peak E ~ Δ1+ Δtip using a Nb tip (Vs = 3.1 mV, Is = 100 pA, and Ve = 0.2 mV). e, FT of (d). f, Differential conductance map measured outside the convoluted superconducting gap using a Nb tip (Vs = 10 mV, Is = 500 pA, and Ve = 0.2 mV). g, FT of (f). FT of the QPI patterns in (e) and (g) exhibit a hexagonal shape, consistent with a prior study on 2 QL Bi2Te3/Fe(Se,Te) (ref. 41). Scale bars: 5 nm (d,f); 1 Å−1 (e, g).
