Phys.org June 17, 2024
Biomimetic nanotechnology and self-assembly advances need chirality. There is a need to develop general methods to characterize chiral building blocks at the nanoscale in liquids such as water. An international team of researchers (UK, Italy, USA – University of Nebraska, Pennsylvania State University) observed chiroptical second-harmonic Tyndall scattering effect in high-refractive-index dielectric nanomaterial Si nanohelices. They provided a theoretical analysis that explained the origin of the effect and its direction dependence, resulting from different specific contributions of “electric dipole–magnetic dipole” and “electric dipole–electric quadrupole” coupling tensors. They narrowed down the number of such terms to 8 in forward scattering and to one in right-angled scattering. According to the researchers their theory can be broadened and adapted to further classes where such scattering has already been observed or is yet to be observed… read more. Open Access TECHNICAL ARTICLE
Graphical abstract. Credit: CS Nano 2024, XXXX, XXX, XXX-XXX, June 17, 2024