Abstract. The High Efficiency and Resolution Multi Element Spectrograph, HERMES, is a facility-class optical spectrograph for the Anglo-Australian Telescope (AAT). It is designed primarily for Galactic Archaeology, the first major attempt to create a detailed understanding of galaxy formation and evolution by studying the history of our own galaxy, the Milky Way. The goal of the GALAH survey is to reconstruct the mass assembly history of the Milky Way through a detailed chemical abundance study of one million stars. The spectrograph is based at the AAT and is fed by the existing 2dF robotic fiber positioning system. The spectrograph uses volume phase holographic gratings to achieve a spectral resolving power of 28,000 in standard mode and also provides a high-resolution mode ranging between 40,000 and 50,000 using a slit mask. The GALAH survey requires an SNR greater than 100 for a star brightness of V ¼ 14 in an exposure time of one hour. The total spectral coverage of the four channels is about 100 nm between 370 and 1000 nm for up to 392 simultaneous targets within the 2-degree field of view. HERMES has been commissioned over three runs, during bright time in October, November, and December 2013, in parallel with the beginning of the GALAH pilot survey, which started in November 2013. We present the first-light results from the commissioning run and the beginning of the GALAH survey, including performance results such as throughput and resolution, as well as instrument reliability. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

A high-quality smart filter for terahertz range with relative tunability reaching 20% has been demonstrated. The filter is based on a narrow transmission band, which originates from a defect mode that appears due to insertion of a single crystal of KTaO 3 into otherwise periodic one-dimensional photonic crystal. Frequencies of defect modes are controlled by the refractive index of the defect: their high tunability is achieved by the strong temperature dependence of the dielectric properties of KTaO 3 . The low losses of KTaO 3 lead to a high peak transmission of the filter. Influence of the defect losses on the properties of the filter is also discussed.

Propagating plasma modes have been observed for the first time in a very thin superconducting film of granular aluminum deposited on a high dielectric constant material in the 100 MHz -1 GHz frequency range. The two-dimensional plasma dispersion relation has been verified, taking into account retardation effects. PACS numbers: 74.40.+k, 74.50.+r, 74.76.Db Until now, in homogeneous superconductors, only one collective mode has been observed, the Carlson-Goldman (CG) mode [1]. The dispersion law is linear

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The design, development and performance evaluation of a novel radio frequency microelectromechanical systems (MEMS) gyroscope, based on a surface acoustic wave resonator (SAWR) and a surface acoustic wave sensor is presented in this paper. Most of the MEMS gyroscopes based on silicon vibratory structures that utilize the energy transfer between the two vibratory modes demand small fabrication tolerances to minimize signal output when there is no rotation (i.e. zero rate output). This 1 cm × 1 cm gyroscope operates based on the principle of a surface acoustic wave (SAW) on a piezoelectric substrate. The SAWR creates SAW standing waves within the cavity space between the interdigital transducers (IDTs). The particles at the anti-nodes of a standing wave experience large amplitudes of vibration perpendicular to the plane of the substrate, which serves as the reference vibrating motion for this gyroscope. A number of metallic dots (proof masses) are strategically positioned at the anti-node locations so that the effect of the Coriolis force due to rotation will amplify the magnitude of the SAW that is generated in the orthogonal direction. The performance of this 74.2 MHz MEMS-IDT gyroscope has been evaluated using rate table and geophone setups , indicating very high sensitivity and dynamic range, which is ideal for many of the commercial applications. Unlike other MEMS gyroscopes, this gyroscope has a planar configuration with no suspended resonating mechanical structures, thereby being inherently robust and shock resistant. In view of its one-layer planar configuration, this gyroscope can be implemented for applications requiring conformal mounting onto a surface of interest.