Single-crystal tellurium provides an elemental platform for examining how electron-phonon coupling and anharmonic phonon scattering appear in Raman spectra and lattice thermal transport. Here, we combine temperature-dependent Raman spectroscopy with first-principles calculations to investigate the phonon response and heat transport of trigonal Te. The calculated electronic structures are strongly modified by spin-orbit coupling, whereas the phonon spectra obtained with and without spin-orbit coupling show only minor differences. Raman measurements reveal a pronounced Fano asymmetry of the $A_1$ mode at low temperature, indicating interference between a discrete phonon and an electronic continuum. The inverse asymmetry parameter $1/q$ decreases toward the Lorentzian limit upon warming, showing that the Fano interference becomes less pronounced at elevated temperatures. Mode-resolved frozen-phonon calculations show that the in-plane $E^1$ and $A_1$ displacements produce appreciable phonon-induced electronic band responses near the $H$ point, where the low-energy bands have strong $p_x/p_y$ character, whereas the $E^2$ displacement produces a weaker response. The temperature-dependent Raman shifts and linewidths are described within a Balkanski-type anharmonic framework, with the linewidths indicating appreciable higher-order anharmonic contributions for selected optical modes. First-principles thermal-transport calculations further show that four-phonon scattering shortens the lifetimes of low-frequency heat-carrying phonons and reduces the lattice thermal conductivity. These results clarify the distinct roles of the mode-selective Fano response and anharmonic phonon scattering in the Raman spectra and lattice thermal transport of single-crystal Te.

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• Spin-orbit coupling
• Thermal conductivity
• Elemental materials
• Density functional calculations
• Raman spectroscopy