Figure 1

(a) The electric (dashed red) and magnetic (solid blue) field lines from an oscillating LSP mode with an electric dipole moment, represented by a cylinder. Also shown are the electric (solid red) and magnetic (dashed blue) field lines associated with incident light linearly polarized at ${45}^{\circ }$. The dipole fields are always orthogonal to each other and are incapable of forming superchiral fields. (b) The electric and magnetic fields can be aligned using two identical nanorods. The rectangle shows a region where the fields are parallel.Reuse & Permissions

Figure 2

The angular dependence of $S_{\chi }^{\mathrm{d}}$ from a dipole (shown as the arrow) for fixed $R$ and $\beta$ calculated using Eq. (10): (a) at resonance for different polarization angles $\psi$ and (b) off resonance for different values of $\Delta \omega /\Gamma$ with $\psi ={45}^{\circ }$, showing a frequency-dependent asymmetry. (c)–(e) Results from a FDTD calculation of $S_{\chi }$ associated with a gold rod ($l=100$ nm, $w=40$ nm, $h=30$ nm) in water on a glass substrate, illuminated with light of linear polarization $\psi ={45}^{\circ }$. Cross sections of the distributions of $S_{\chi }$ through the rod center are shown: (c) in the $x$–$y$ plane on resonance ($\lambda =790$ nm) (d) in the $y$–$z$ plane on resonance, and (e) in the $y$–$z$ plane off resonance ($\lambda =820$ nm), where the dashed line shows the contour $S_{\chi }=-1$.Reuse & Permissions

Figure 3

(a) Three gold nanorods arranged to produce superchiral fields between rods 1 and 2. Nanorods 1 and 2 are in water, and nanorod 3 is embedded in the glass substrate symmetrically below rods 1 and 2. All rods have $h=30$ nm and $w=40$ nm, with rods 1 and 2 having $l=86$ nm, separated by 40 nm, and rod 3 having $l=90$ nm and being 10 nm below the substrate surface. (b) $S_{\chi }$ averaged over the volume between rods 1 and 2 as a function of wavelength for four orientations $\psi$ of linear polarization. (c) $S_{\chi }$ on resonance as a function of position along the edge of rod 1 [shown as the dashed line in (a)] for $\psi ={135}^{\circ }$. The maximum occurs at the corner of the rod. The band indicates the position of the nanorod face.Reuse & Permissions