Fig. 4: Optical activity spectroscopy.
a–c, CD (top) and ORD (bottom) images of the left-handed, right-handed and racemic arrays (from left to right) at different wavelengths: 650 nm (a), 690 nm (b) and 720 nm (c). d, CD (top) and ORD (bottom) spectra of the chiral nanostructures measured with polarization-sensitive holography (dots). Each dot represents the averaged signal on the array of nanostructures in the corresponding image. Top: solid lines correspond to the CD spectra acquired with a conventional CD spectrometer as a comparison. The dashed lines indicate the wavelengths of the CD and ORD images shown in a–c. Scale bar, 50 μm.
