We demonstrate the bulk self-alignment of dispersed gold nanorods imposed by the intrinsic cylindrical micelle selfassembly in nematic and hexagonal liquid crystalline phases of anisotropic fluids. External magnetic field and shearing allow for alignment and realignment of the liquid crystal matrix with the ensuing long-range orientational order of well-dispersed plasmonic nanorods. This results in a switchable polarization-sensitive plasmon resonance exhibiting stark differences from that of the same nanorods in isotropic fluids. The device-scale bulk nanoparticle alignment may enable optical metamaterial mass production and control of properties arising from combining the switchable nanoscale structure of anisotropic fluids with the surface plasmon resonance properties of the plasmonic nanorods.KEYWORDS Nanorods, liquid crystals, optical metamaterials, self-assembly, plasmonic nanoparticles H aving predesigned structural units different from those in a conventional matter, metamaterials exhibit many unusual properties of interest from both fundamental science and applications standpoints. However, manufacturing such bulk optical metamaterials with three-dimensional (3D) structure 1-4 using lithography techniques presents a significant challenge, especially for the large-scale production. Mass production of bulk optical metamaterials from self-aligning and self-assembling nanoparticles is poised to revolutionize scientific instruments, technologies,andconsumerdevices.5-7 Althoughthemetamaterial self-assembly from nanoparticles remains a significant challenge, recent advances in colloidal science show that it may be realized and the emerging nanoscale alignment and assembly approaches utilize surface monolayers, 8,9 stretched polymer films, 10,11 and functionalized nanoparticles 12,13 but are usually restricted to only short-range ordering, twodimensional rather than three-dimensional assembly, and limited switching.7 Tunable metamaterials may potentially be obtained by nanoparticle self-assembly in liquid crystals (LCs) 14 through the LC-mediated realignment and rearrangement of incorporated nanoparticles in response to applied fields. However, experimental realization of such self-assembling switchable metamaterial composites is lacking. In this work, we demonstrate spontaneous long-range orientational ordering of gold nanorods (GNRs) dispersed in surfactant-based lyotropic LCs and use polarizing optical microscopy, darkfield microscopy, spectroscopy, and freezefracture transmission electron microscopy (FFTEM) to study these composites on the scales ranging from nanometers to millimeters. We find that the anisotropic fluids in both columnar hexagonal and nematic LC phases impose nematic-like long-range orientational ordering of GNRs with no correlation of their centers of mass but with the GNRs aligning along the LC director n (a unit vector describing the average local orientation of cylindrical micelles forming the LC), Figure 1. The unidirectional alignment of nanorods with high order parameter is...

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We demonstrate the first (to our knowledge) general purpose full-field reflection-mode extreme ultraviolet (EUV) microscope based on coherent diffractive imaging. This microscope is capable of nanoscale amplitude and phase imaging of extended surfaces at an arbitrary angle of incidence in a noncontact, nondestructive manner. We use coherent light at 29.5 nm from high-harmonic upconversion to illuminate a surface, directly recording the scatter as the surface is scanned. Ptychographic reconstruction is then combined with tilted plane correction to obtain an image with amplitude and phase information. The image quality and detail from this diffraction-limited tabletop EUV microscope compares favorably with both scanning electron microscope and atomic force microscope images. The result is a general and completely extensible imaging technique that can provide a comprehensive and definitive characterization of how light at any wavelength scatters from a surface, with imminent feasibility of elemental imaging with few-nanometer resolution. OCIS codes: (120.5050) Phase measurement; (180.0180) Microscopy; (180.7460) X-ray microscopy; (190.2620) Harmonic generation and mixing. http://dx.