Enhanced and tunable surface plasmons in two-dimensional Ti3C2 stacks: Electronic structure versus boundary effects

The dielectric response of two-dimensional (2D) Ti3C2 stacked sheets was investigated by high-resolution transmission electron energy-loss spectroscopy and ab initio calculations in the 0.2–30-eV energy range. Intense surface plasmons (SPs), evidenced at the nanometer scale at energies as low as 0.3 eV, are shown to be the dominant screening process up to at least 45-nm-thick stacks. This domination results from a combination of efficient …