Fig. 3: DFT calculation of electron-TA phonon coupling driven TPT.
From: Incommensurate Transverse Peierls Transition and Signature of Chiral Charge Density Wave in EuAl4
a Electronic band structure of non-magnetic sister compound SrAl4. Light blue, purple, and grey marks represent Al \(3{p}_{x,y}\)-orbitals, Al \(3{p}_{z}\)-orbital, and Sr 5s-orbital, respectively. The Brillouin zone and high symmetry point in momentum space are shown in (b). The “nesting” of the linearly dispersed semi-Dirac bands give rise to a peak in the calculated charge susceptibility, \({\chi }_{0}^{{\prime} {\prime} }\). The susceptibility peak position matches the calculated lattice instability of the TA phonon shown in (c, d). Dashed grey curve and solid black curves are calculated for different electron temperatures. The negative TA phonon at σ = 1 mRy supports electron-TA phonon coupling driven TPT and is consistent with experimental observations.
