Giant enhancement of THz-frequency optical nonlinearity by phonon polariton in ionic crystals.

ABSTRACT: The field of nonlinear optics has grown substantially in past decades, leading to tremendous progress in fundamental research and revolutionized applications. Traditionally, the optical nonlinearity for a light wave at frequencies beyond near-infrared is observed with very high peak intensity, as in most materials only the electronic nonlinearity dominates while ionic contribution is negligible. However, it was shown that the ionic contribution to nonlinearity can be much larger than the electronic one in microwave experiments. In the terahertz (THz) regime, phonon polariton may assist to substantially trigger the ionic nonlinearity of the crystals, so as to enhance even more the nonlinear optical susceptibility. Here, we experimentally demonstrate a giant second-order optical nonlinearity

SUBMITTER: Lu Y 

PROVIDER: S-EPMC8155090 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature