Fig. 4: QSB QPI for Δ(k) identification in UTe2.
From: Odd-parity quasiparticle interference in the superconductive surface state of UTe2
a–f, Measured a(r, V) at the (0–11) cleave plane of UTe2 at bias voltages \(\left|V\right|=\) 0 µV (a), 50 µV (b), 100 µV (c), 150 µV (d), 200 µV (e) and 250 µV (f). The setpoint is Vs = 3 mV and I = 200 pA. g, Predicted QPI patterns for a B2u QSB at the (0–11) SBZ of UTe2 at energies \(\left|E\right|=\) 0, 50, 100, 150, 200 and 250 µeV (Methods and Extended Data Figs. 3–6). We take into account the finite radius of the scan tip in simulations by applying a 2D Gaussian to the \(N\left({\bf{q}},E\right)\) maps (Methods and Extended Data Fig. 6). The existing QPI wavevector \({{\bf{q}}}_{2}\) is identified as the maxima position (brown circle) in the QPI simulation. h, Measured a(q, V) at the (0–11) cleave plane of UTe2 at bias voltages \(\left|V\right|=\) 0, 50, 100, 150, 200 and 250 µV. The setpoint is Vs = 3 mV and I = 200 pA. These QPI data are derived by Fourier transformation of a(r, V) data in a–f. Each QPI wavevector in this FOV, \({{\bf{q}}}_{1}\) (red), \({{\bf{q}}}_{2}\) (brown) and \({{\bf{q}}}_{5}\) (cyan), is identified as the maxima position (coloured circles) in the experimental QPI data. In particular, \({{\bf{q}}}_{1}\) is a characteristic only of the B3u superconducting state, and it only exists inside the energy gap. \({{\bf{q}}}_{1}\) cannot be due to a pair density wave (Methods). i, Predicted QPI patterns for a B3u QSB at the (0–11) SBZ of UTe2 at energies \(\left|E\right|=\) 0, 50, 100, 150, 200 and 250 µeV (Methods and Extended Data Figs. 3–6). Each QPI wavevector, \({{\bf{q}}}_{1}\), \({{\bf{q}}}_{2}\) and \({{\bf{q}}}_{5}\), is identified as the maxima position (coloured circles) in the QPI simulation. We take into account the finite radius of the scan tip in simulations by applying a 2D Gaussian to the \(N\left({\bf{q}},E\right)\) maps (Methods and Extended Data Fig. 6).
