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We demonstrate the combination of a hemispherical solid immersion lens with a micro-photoluminescence setup. Two advantages introduced by the SIL, an improved resolution of 0.4 times the wavelength in vacuum and a 5 times enhancement of the…

Optics · Physics 2009-11-07 S. Moehl , Hui Zhao , B. Dal Don , S. Wachter , H. Kalt

Determination of refractive index of micro-disks of a calcinated ($1100^\circ$C in air) photo-resist SZ2080$^\mathrm{TM}$ was carried out using transmission and reflection spectroscopy. Interference fringes at specific…

The authors measured the transport properties of single-walled carbon nanotube (SWCNT) films in the microwave frequency range from 10 MHz to 30 GHz by using the Corbino reflection technique from temperatures of 20-400 K. Based on the real…

Materials Science · Physics 2009-09-14 Hua Xu , Liangbing Hu , Steven M. Anlage , George Gruner

We describe a micro-fabrication method to create concave features with ultra-low surface roughness in silica, either on the end facets of optical fibers or on flat substrates. The machining uses a single focused CO2 laser pulse. Parameters…

We propose a thin, compact, broadband, polarization and angle insensitive metamaterial absorber based on a tungsten reflector, silicon spacer and a top pattern composed of a double square-like ring resonator utilizing nickel(Ni). In such a…

Optics · Physics 2022-06-02 Henrik Parsamyan

We report on the microscopic surface structure of carbon-fiber-reinforced silicon carbide (C/SiC) composite mirrors that have been improved for the Space Infrared Telescope for Cosmology and Astrophysics (SPICA) and other cooled telescopes.…

Astrophysics · Physics 2009-06-23 Keigo Enya , Takao Nakagawa , Hidehiro Kaneda , Takashi Onaka , Tuyoshi Ozaki , Masami Kume

Ground-based millimeter and sub-millimeter telescopes are attempting to image the sky with ever-larger cryogenically-cooled bolometer arrays, but face challenges in mitigating the infrared loading accompanying large apertures. Absorptive…

Instrumentation and Methods for Astrophysics · Physics 2014-07-23 Z. Ahmed , J. A. Grayson , K. L. Thompson , C. L. Kuo , G. Brooks , T. Pothoven

We present results of an extensive suite of numerical simulations that probe square-tiled microwave absorber performance as a function of material properties, frequency, geometry, and unit cell size. The work, which probes both specular…

Instrumentation and Methods for Astrophysics · Physics 2025-11-10 Gaganpreet Singh , Rustam Balafendiev , Mahesh Singh Bist , Thomas J. L. J. Gascard , Gagandeep Kaur , Vid Primožič , Jon E. Gudmundsson

We design plano-concave silicon lenses with coupled gradient-index plasmonic metacoatings for ultrawide apertured focusing utilizing a reduced region of $\sim 20 \lambda^2$. The anomalous refraction induced in the planar input side of the…

Organic solar cells (OSCs) are uniquely suited for semitransparent applications due to their adjustable absorption spectrum. However, most high-performance semitransparent cells reported to date are based on materials that have shown high…

With a conventional lens sharpness of the image is always limited by the wavelength of light. An unconventional alternative to a lens, a slab of negative refractive index material, has the power to focus all Fourier components of a 2D…

Optics · Physics 2025-07-03 JB Pendry

Mobile operators are poised to leverage millimeter wave technology as 5G evolves, but despite efforts to bolster their reliability indoors and outdoors, mmWave links remain vulnerable to blockage by walls, people, and obstacles. Further,…

Networking and Internet Architecture · Computer Science 2022-09-27 Kun Woo Cho , Mohammad H. Mazaheri , Jeremy Gummeson , Omid Abari , Kyle Jamieson

Conventional surface-relief gratings are inefficient at deflecting normally-incident light by large angles. This constrains their use in many applications and limits the overall efficiency of any optical instrument integrating gratings.…

Optics · Physics 2021-11-19 Ashutosh Patri , Stephane Kena-Cohen , Christophe Caloz

Demand for lightweight, highly reflective and mechanically compliant mirrors for optics experiments has seen a significant surge. In this aspect, photonic crystal (PhC) membranes are ideal alternatives to conventional mirrors, as they…

Fundamentally new technology is described for constructing low areal mass density (1kg/m^2), high precision (< 10micron RMS) reflectors scalable to large apertures (10 to 20 meters) for use as the primary element of a telescope system. A…

Astrophysics · Physics 2009-09-25 Mark Dragovan

High refractive index contrast optical microdisk resonators fabricated from silicon-on-insulator wafers are studied using an external silica fiber taper waveguide as a wafer-scale optical probe. Measurements performed in the 1500 nm…

Conventional microscope objective lenses are diffraction limited, which means that they cannot resolve features smaller than half the illumination wavelength. Under white light illumination, such resolution limit is about 250-300 nm for an…

Instrumentation and Detectors · Physics 2021-08-26 Bing Yan , Zengbo Wang , Alan Parker , Yukun Lai , John Thomas , Liyang Yue , James Monks

We present the design, implementation and data taking performance of the MIcrowave Detection of Air Showers (MIDAS) experiment, a large field of view imaging telescope designed to detect microwave radiation from extensive air showers…

We use a 1030 nm laser with 7 ps pulse duration and average power up to 100 W to ablate pyramid-shape subwavelength structures (SWS) on alumina and sapphire. The SWS give an effective and cryogenically robust anti-reflection coating in the…

Applied Physics · Physics 2021-05-18 Qi Wen , Elena Fadeeva , Shaul Hanany , Jürgen Koch , Tomotake Matsumura , Ryota Takaku , Karl Young

Negative refraction is known to occur in materials that simultaneously possess a negative electric permittivity and magnetic permeability; hence they are termed negative index materials. However, there are no known natural materials that…