Ab initio calculations and angle-resolved photoemission experiments demonstrate that the bulk and surface electronic structure of Weyl semimetal candidate ${\mathrm{MoTe}}_2$ changes significantly by tuning the chemical potential by less than 0.4 eV. Calculations indicate that several Lifshitz transitions can occur among multiple electron and hole Fermi pockets of differing orbital character. Experiments show that 18% Nb-Mo substitution reduces the occupation of bulk and (001) surface bands, effectively producing a quasirigid band shift of $\approx 0.2\mathrm{eV}$. Orbital character and dimensionality of the bulk bands is examined by soft-x-ray angle-resolved photoemission with control of the excitation light polarization. Deposition of alkali-metal atoms on the surface produces electron binding energy shifts consistent with increased band filling. The results indicate that multiple regimes of electronic properties can be easily accessed in this versatile, layered material.

Close

PrevNext

View figure in article

• Fermi surface
• Spin-orbit coupling
• Surface states
• Transition metal dichalcogenides
• Angle-resolved photoemission spectroscopy
• First-principles calculations