Romao Carl P, Juraschek Dominik M
Department of Materials, ETH Zurich, CH-8093 Zurich, Switzerland.
School of Physics and Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel.
ACS Nano. 2024 Oct 29;18(43):29550-29557. doi: 10.1021/acsnano.4c05978. Epub 2024 Oct 18.
Chiral properties have seen increasing use in recent years, leading to the emerging fields of chiral quantum optics, plasmonics, and phononics. While these fields have achieved manipulation of the chirality of light and lattice vibrations, controlling the chirality of materials on demand has yet remained elusive. Here, we demonstrate that linearly polarized phonons can be used to induce geometric chirality in achiral crystals when excited with an ultrashort laser pulse. We show that nonlinear phonon coupling quasistatically displaces the crystal structure along phonon modes that reduce the symmetry of the lattice to that of a chiral point group corresponding to a chiral crystal. By reorienting the polarization of the laser pulse, the two enantiomers can be induced selectively. Therefore, enable the light-induced creation of chiral crystal structures and therefore the engineering of chiral electronic states and optical properties.
近年来，手性特性的应用越来越广泛，催生了手性量子光学、等离激元学和声子学等新兴领域。虽然这些领域已经实现了对光的手性和晶格振动的操控，但按需控制材料的手性仍然难以实现。在此，我们证明，当用超短激光脉冲激发时，线性偏振声子可用于在非手性晶体中诱导几何手性。我们表明，非线性声子耦合会沿声子模式准静态地移动晶体结构，从而将晶格对称性降低到与手性晶体相对应的手性点群的对称性。通过重新定向激光脉冲的偏振，可以选择性地诱导出两种对映体。因此，实现了光诱导手性晶体结构的创建，进而实现了手性电子态和光学性质的工程设计。
