The first experimental sub-diffraction imaging using superlens was demonstrated in near-field images with 60 nm half-pitch resolution in UV range as shown in Fig. 5 [52].
From these two facts, evanescent waves in the negative diffraction order are strongly transmitted compared to propagating waves in the order 0, enabling sub-diffraction imaging.
When p is negative and the grating wavenumber is large enough, the wavevectors of the transmitted waves is reduced enough to propagate, resulting in far-field sub-diffraction imaging.
Due to this abnormal property, there have been many researches and it was discovered that hyperbolic metamaterials can realize enhancement in spontaneous emission, very large photonic density of states [38, 82 85], thermal engineering [86 88], and of course sub-diffraction imaging.
Additional applications of NMF and other matrix factorization techniques to other X-ray diffraction imaging techniques promise to reveal a wealth of structural information.
Although electron, neutron, and X-ray scattering are based on different physical processes, the resulting diffraction patterns are analyzed using the same coherent diffraction imaging techniques.
Sub-diffraction imaging using hyperlens was experimentally demonstrated in UV [92, 93] and visible [94, 95] frequency range.
Hyperbolic polaritons confined in a sub-diffractional volume were observed in a crystal of hexagonal boron nitride [114] and the sub-diffraction imaging lenses in IR frequency range were demonstrated [114 116].
He uses supermicroscopy, sub-diffraction imaging, particle tracking, biochemistry and genetics to follow the motion and changing structure of single molecules in living cells.
D. Schurig and D. R. Smith, Sub-diffraction imaging with compensating bilayers, New Journal Of Physics, vol. 7 (August, 2005) [abs].
The first theoretical study about sub-diffraction imaging using metamaterials was done by Pendry [41, 42].
