Author(s): Song, Z; Sun, X; Wang, LW | Abstract: Twisted bilayers of van der Waals materials have recently attracted great attention due to their tunable, strongly correlated phenomena. Here, we investigate the chirality-specific physics in three-dimensional moire superlattices induced by Eshelby twist. Our direct density functional theory calculations reveal helical rotation leads optical circ...

Sum-frequency generation in isotropic media is in the electric-dipole approximation the only symmetry allowed for chiral systems. We demonstrate that the sum-frequency intensity from an optically active liquid depends quadratically on the difference in concentration of the two enantiomers. The dominant contribution to the signal is found to be due to the chirality specific electric-dipolar thre...

We manufacture large-area plasmonic structures featuring 3-dimensional chirality by colloidal nanohole lithography. By varying the polar rotating speed of the samples during gold evaporation, we can fabricate spiral-type ramp nanostructures. The optical properties show chiroptical resonances in the 100 to 400 THz frequency region (750 to 3000 nm), with circular dichroism values of up to 13%. Ou...

Inherently chiral calixarenes, whose chirality is based on the absence of a planar symmetry or an inversion center in the molecules as a whole through the asymmetric array of several achiral groups upon the three-dimensional calix-skeletons, are challenging and attractive chiral molecules, because of their potential in supramolecular chemistry. The synthesis and optical resolution of all variet...

Using predesigned trains of femtosecond optical pulses, we have selectively excited coherent phonons of the radial breathing mode of specific-chirality single-walled carbon nanotubes within an ensemble sample. By analyzing the initial phase of the phonon oscillations, we prove that the tube diameter initially increases in response to ultrafast photoexcitation. Furthermore, from excitation profi...

We investigate a force that has been predicted to discriminate molecules by their chirality when they are in the presence of an optical field with a polarization-helicity gradient. We investigate several experimental geometries for observing evidence of this force via enantiometer separation in racemic mixtures. We do this with singularoptical beams carrying a polarization helicity gradient acr...

Three dimensional helical chiral metamaterials resulted in effective manipulation of circularly polarized light in the visible infrared for advanced nanophotonics. Their potentialities are severely limited by the lack of full rotational symmetry preventing broadband operation, high signal-to-noise ratio and inducing high optical activity sensitivity to structure orientation. Complex intertwined...

Time-harmonic electromagnetic waves are scattered by a homogeneous chiral obstacle. The reciprocity principle, the basic scattering theorem and an optical theorem are proved. These results are used to prove that if the chirality measure of the obstacle is real, then the far-"eld operator is normal. Moreover, it is shown that the eigenvalues of the far-"eld operator are the same as the eigenvalu...

We investigate the optical response of gold nanorod (AuNR) dimers assembled in parallel on a DNA origami template. Plasmonic circular dichroism (CD) was found to be highly dependent on the orientation of the dimers relative to the DNA axis and the inter-rod distances. Dipole-dipole distances play a critical role in the induced plasmonic chirality. The orientation dependence of induced CD was fu...

The first molecular material with the coexistence of ferromagnetism, metal-like conductivity, and chirality has been prepared using an organic/inorganic approach. In this case, a two-dimensional packing of chiral organic radical cations (responsible for both the electrical conductivity and optical activity) was assembled with a layered bimetallic oxalate-based anionic network (responsible for t...