Figure 2: Bandgaps in single-layer film and bulk TiSe2.
From: Charge density wave transition in single-layer titanium diselenide
(a) Comparison of ARPES spectra and calculated bands (blue dashed curves) for single-layer TiSe2 in both the normal and CDW phases. The data were taken with 58 eV photons. (b) Comparison of ARPES spectra and calculated bands (cyan dashed curves) for bulk TiSe2. The photon energies used were 58, 61, 67 and 61 eV for the top left, top right, bottom left and bottom right panels, respectively. (c) Constant-energy-contour maps around 
for film (yellow-colour-coded) and bulk (red-colour-coded) at energy of −1.0 eV, taken with 58 eV photons. (d) Dispersions of the valence band maxima of single-layer TiSe2 as a function of kz (or photon energy). (e) Atom displacements in the CDW phase. Se1 and Se2 correspond to Se atoms in the top and bottom layers, respectively. The length of each arrow indicates the magnitude of the displacement amplified by 50 times.
