Ghalgaoui, Ahmed Yang, Fan Pilch, Patrick Kang, Taehee Runge, Matthias Yue, Shengying Chen, Yubi Yang, Yunkun Xiu, Faxian Sheng, Xian-Lei Yang, Shengyuan A. Wang, Zhe 2025-08-20T03:11:13Z 2025-08-20T03:11:13Z 2025-08-20 2025-07 2469-9950 https://pubs.kist.re.kr/handle/201004/152963 The coherent lattice dynamics in the three-dimensional (3D) Dirac semimetal Cd3As2 is investigated in the nonperturbative regime of light-matter interaction using coherent two-dimensional terahertz (THz) spectroscopy, as a function of time delay and field strength. The phase-resolved nonlinear signal reveals a coherent phonon mode at 1.48 THz, corresponding to the B2g Raman-active mode, characterized by the periodic motion of two cadmium atoms in the substructure toward and away from two cadmium-vacant sites. The interaction of a strong THz electric field with the 3D Dirac semimetal Cd3As2 leads to transient charge carrier imbalance via tunneling ionization, which results in a displacive force that drives the lattice dynamics of a noninteracting Raman-active mode. The selective excitation of otherwise inaccessible phonon modes enables precise control over the material's properties at the atomic level, opening new pathways to manipulate its topological characteristics. English AMER PHYSICAL SOC Nonlinear terahertz phononics in the Dirac semimetal Cd3As2 Article 10.1103/y2bx-tkkq 1 Physical Review B, v.112, no.4 Physical Review B 112 4 Y scie scopus 001539428200002 Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Materials Science Physics Article BILBAO CRYSTALLOGRAPHIC SERVER DISPLACIVE EXCITATION COHERENT MOBILITY DRIVEN