We explore the Fano resonance in ${\mathrm{ZrTe}}_5$, using terahertz Raman scattering measurements. We identified two closely spaced ${\mathrm{B}}_{2\mathrm{g}}$ phonon modes, ${\mathrm{B}}_{2\mathrm{g}}$ I and ${\mathrm{B}}_{2\mathrm{g}}$ II, around 9 meV and 11 meV, respectively. Interestingly, only ${\mathrm{B}}_{2\mathrm{g}}$ I exhibited the Fano resonance, an outcome of quantum interference between discrete phonon modes and continuous electronic excitations. This is consistent with the much stronger electron-phonon coupling of ${\mathrm{B}}_{2\mathrm{g}}$ I mode demonstrated by first-principles calculations. Additionally, temperature-dependent measurements highlight an enhanced Fano asymmetry at elevated temperatures, contributed by the thermal renormalization of the band structure and electron-phonon coupling. This study offers insights into the complex interrelation of electron-phonon coupling, thermal effects, and Fano resonances in topological materials.

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• Electron-phonon coupling
• Electronic structure
• Fano resonance
• First-principles calculations
• Optical phonons
• Phase transitions
• Topological materials
• Dirac semimetal
• Band structure methods
• Density functional theory
• Raman spectroscopy