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1 advances.sciencemag.org/cgi/content/full/2/8/e /dc1 Supplementary Materials for Three-dimensional all-dielectric metamaterial solid immersion lens for subwavelength imaging at visible frequencies Wen Fan, Bing Yan, Zengbo Wang, Limin Wu Published 12 August 2016, Sci. Adv. 2, e (2016) DOI: /sciadv This PDF file includes: fig. S1. Wafer pattern used for evaluating the magnification factor and field of view of a TiO2 msil. fig. S2. Estimation of the effective refractive index and particle volume fraction of a TiO2 msil. fig. S3. Field of view of a TiO2 msil. fig. S4. The limiting resolution obtained with a TiO2 hemispherical msil. fig. S5. The super-resolution images obtained with a TiO2 super-hemispherical msil. fig. S6. Direct imaging of wafer patterns by an optical microscope. fig. S7. Direct optical observation of 50-nm latex beads located on the surface of a Blu-ray disk. fig. S8. Comparisons of TiO2 hemispherical msil assembled from 15- or 45-nm anatase TiO2 nanoparticles. fig. S9. Nano solid-fluid assembly for the TiO2 optical fiber. fig. S10. Characterizations of 15-nm anatase TiO2 nanoparticles.

2 Supplementary Figures fig. S1. Wafer pattern used for evaluating the magnification factor and field of view of a TiO2 msil. (a) SEM image of the wafer pattern, which shows 400-nm-wide squares with a pitch of 200 nm. (b) Optical micrograph of the wafer pattern at a magnification of 2,100, indicating that the conventional optical microscopy will fail to reveal the shape of the squares due to the Abbe diffraction limit.

3 fig. S2. Estimation of the effective refractive index and particle volume fraction of a TiO2 msil. The experimentally observed correlation between the magnification factor and the height-to-width ratio for msil of 10 μm (red), 15 μm (green) and 20 μm (blue) in Fig. 2. Theoretical curve (black) is obtained using geometry optics analysis with an effective index of Moreover, the effective index of msil nmsil can be expressed as nm SIL na ir Va ir npa rticle Vparti cle, where n air =1 is the refractive index of air, n particle =2.55 is the refractive index of anatase TiO2 nanoparticles at λ=550 nm, V air is the volume fraction of air in msil and V particle is the volume fraction of TiO2 nanoparticles in msil. Therefore, we can calculate that V particle =61.3%.

4 fig. S3. Field of view of a TiO2 msil. In Fig. 2, the field of view of msil increases almost linearly with an increase in the width of msil from 10 μm to 20 μm.

5 fig. S4. The limiting resolution obtained with a TiO2 hemispherical msil. Optical micrographs focused on (a) the wafer pattern, and (b) the 1.8 times magnified virtual image created by a TiO2 hemispherical msil. The corresponding SEM images of (c) the hemispherical msil and (d) the wafer pattern with 75 nm features, the dashed circle in (d) represents the field of view seen in (b). The hemispherical msil has a width of 15 μm. The results indicate that the hemispherical msil with a magnification factor of 1.8 is insufficient to resolve the features below 75 nm.

6 fig. S5. The super-resolution images obtained with a TiO2 super-hemispherical msil. Optical micrographs of a TiO2 super-hemispherical msil focused on the surface of a wafer pattern with 50 nm features (without gold coating) under an illumination of (a) white light, (b) green light (λ~540 nm) or (c) blue light (λ~470 nm), respectively. The super-hemispherical msil has a magnification factor of 3.0 and a width of 15 μm. The optical micrographs were taken using an Olympus BX63 light microscope equipped with a 5-megapixel CCD camera (Olympus, DP26) and a 100 objective lens (Olympus, LMPlanFL N, NA=0.8).

7 fig. S6. Direct imaging of wafer patterns by an optical microscope. Optical micrographs of a wafer pattern with (a to c) 50 nm features (without gold coating) or (e to g) 45 nm features (after gold coating) under an illumination of (a, e) white light, (b, f) green light (λ~540 nm) or (c, g) blue light (λ~470 nm), respectively. The optical micrographs were taken using an Olympus BX63 light microscope equipped with a 5-megapixel CCD camera (Olympus, DP26) and a 100 objective lens (Olympus, LMPlanFL N, NA=0.8). SEM images of the corresponding wafer pattern with (d) 50 nm features or (h) 45 nm features. The results indicate that the optical microscope is unable to resolve the subwavelength details of the wafer patterns.

8 fig. S7. Direct optical observation of 50-nm latex beads located on the surface of a Blu-ray disk. (a) Optical micrograph and (b) SEM image of 50 nm polystyrene latex beads (Coulter N4 size control standards, Beckman Coulter, USA) located on the surface of a blank Blu-ray disk, as indicated by the arrows. The msil has a magnification factor of 2.5 and a width of 18 μm. The optical micrograph was taken using an Olympus BX63 light microscope.

9 fig. S8. Comparisons of TiO2 hemispherical msil assembled from 15- or 45-nm anatase TiO2 nanoparticles. Optical micrographs of a Blu-ray disc observed through hemispherical msil composed of (a) 15 nm or (b) 45 nm anatase TiO2 nanoparticles, respectively. High magnification SEM images of (c and d) the top surfaces, and (e and f) the bottom surfaces of the hemispherical msil composed of 15 nm or 45 nm TiO2 nanoparticles, respectively. The results indicate that 15 nm TiO2 nanoparticles will provide a denser packing structure of nanoparticles and better imprinting of nano-scale features, leading to more clear observation of subwavelength details.

10 fig. S9. Nano solid-fluid assembly for the TiO2 optical fiber. (a) SEM image of a 260-µmdiameter TiO2 wire prepared by injection molding of 15 nm TiO2 nano-solid-fluid using a 25 G plastic needle. (b) Photograph obtained by illuminating one end of a TiO2 wire with 650 nm laser, indicating that the TiO2 wire can be used as optical fiber for low-loss light transmission over long distances. Inset: The optical micrograph indicates that the TiO2 wire is highly transparent to visible light.

11 fig. S10. Characterizations of 15-nm anatase TiO2 nanoparticles. (a) Number-average particle size distribution of the anatase TiO2 nanoparticles measured by Zetasizer Nano ZS90 (Malvern instruments Ltd., UK), showing a peak at 15 nm. (b) Typical HRTEM image of a single anatase TiO2 nanoparticle performed on a Tecnai G2 F20 (Philips, Holland), indicating the nanocrystal has a highly crystalline structure and an approximately spherical shape. (c) High magnification SEM image of the dense and short-range order arrangement of TiO2 nanoparticles in msil.