Fig. 3: Tuning the Kondo effect and correlations.
From: Modulated Kondo screening along magnetic mirror twin boundaries in monolayer MoS2
a, dI/dV spectrum of non-degenerate states (blue circles) of an MTB with L = 6.5 nm, ε = −39.0 meV, U = 110.0 meV, γ = 10.8 meV. Coulomb energy U, energy spacing ε from EF, and full-width at half-maximum of the main Lorentzian peak γ are indicated, defining the parameters needed for an NRG simulation. Lorentzian functions fitted to the inner slope of the peaks are shown, from which the full-width at half-maximum γ is extracted. b, Coulomb gap (U) for MTBs of different lengths (L). The a/L fit gives a = 793 meV nm = 0.55e2/(4πε0), where e is the electron charge. c, Peak position of non-degenerate states below (ε) and above (ε + U) the Fermi energy. As L increases, the gap U between the states shrinks. d, Correlation strength U/γ of MTBs, calculated for MTBs with U and γ obtained from Lorentzian fits. e, Peak position of the non-degenerate states in units of γ. For all the boundaries, ∣ε∣ ≥ γ/4 and ∣ε + U∣ ≥ γ/4, placing them in the Kondo regime. Each data point for U, ε or γ represents the value extracted from a Lorentzian fit to the spectra, with a minimum error corresponding to the experimental resolution, whereas the errors in L are based on the accuracy with which we were able to determine the particular length of a boundary. STM/STS parameters: for a, Vset = 200 mV, Iset = 0.2 nA, Vmod = 1.0 mV. All the spectra used in b–e were measured with Vmod = 1.0 mV, but under different stabilization voltages and currents.
