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Madrid, Spain

Jofre M.,ICFO - Institute of Photonic Sciences | Gardelein A.,ICFO - Institute of Photonic Sciences | Anzolin G.,ICFO - Institute of Photonic Sciences | Amaya W.,Multimedia University | And 18 more authors.
Optics Express | Year: 2011

A novel integrated optical source capable of emitting faint pulses with different polarization states and with different intensity levels at 100 MHz has been developed. The source relies on a single laser diode followed by four semiconductor optical amplifiers and thin film polarizers, connected through a fiber network. The use of a single laser ensures high level of indistinguishability in time and spectrum of the pulses for the four different polarizations and three different levels of intensity. The applicability of the source is demonstrated in the lab through a free space quantum key distribution experiment which makes use of the decoy state BB84 protocol. We achieved a lower bound secure key rate of the order of 3.64 Mbps and a quantum bit error ratio as low as 1.14×10-2 while the lower bound secure key rate became 187 bps for an equivalent attenuation of 35 dB. To our knowledge, this is the fastest polarization encoded QKD system which has been reported so far. The performance, reduced size, low power consumption and the fact that the components used can be space qualified make the source particularly suitable for secure satellite communication. © 2011 Optical Society of America. Source


Fraser G.W.,University of Leicester | Carpenter J.D.,University of Leicester | Rothery D.A.,Open University Milton Keynes | Pearson J.F.,University of Leicester | And 49 more authors.
Planetary and Space Science | Year: 2010

The Mercury Imaging X-ray Spectrometer (MIXS) on the BepiColombo Mercury Planetary Orbiter (MPO) will measure fluorescent X-ray emission from the surface of Mercury in the energy range 0.5-7.5 keV, which is induced by incident solar X-rays and solar wind electrons and protons. These X-rays will reveal the elemental composition of the surface of Mercury and aid the determination of the planet's evolution. MIXS is a two component instrument. A collimated channel (MIXS-C) provides measurements on scales of 70-270 km, sufficient to separate the major Mercurian terrains. A second channel (MIXS-T) is the first imaging X-ray telescope for planetary remote sensing and will make measurements on spatial scales of less than 10 km for major elements during solar flares, sufficient to isolate surface landforms, such as craters and their internal structures. The spatial resolution achieved by MIXS-T is made possible by novel, low mass microchannel plate X-ray optics, in a Wolter type I optical geometry. MIXS measurements of surface elemental composition will help determine rock types, the evolution of the surface and ultimately a probable formation process for the planet. In this paper we present MIXS and its predicted performance at Mercury as well as discussing the role that MIXS measurements will play in answering the major questions about Mercury. © 2009 Elsevier Ltd. All rights reserved. Source


Gonzalo R.Z.,CSIC - National Institute of Aerospace Technology | Tomas B.D.,CSIC - National Institute of Aerospace Technology | Carmen P.S.,CSIC - National Institute of Aerospace Technology | Rene R.G.,CSIC - National Institute of Aerospace Technology | And 6 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

A LED based illumination system in which five Galilean collimation systems have been used is reported on. It is part of a turbulence simulator for the evaluation of on ground telescopes instrumentation developed by INTA (optics) and LIDAX (opto-mechanics) for the IAC called IACATS. The illumination requirements (some visible and infrared lines) allow the use of five different LEDs (red, green, blue and two infrareds). In order to optimize the illumination level of each wavelength, a Galilean collimating optical configuration was constructed for each wavelength channel. The IACATS instrument simulates a scene consisting of a set of different binary stars simulating the required angular separation between them, ant their spectral characteristics. As a result, a visible and infrared multi-spectral illumination system has been integrated as a part of the turbulence simulator, and the features (opto-mechanical) and illumination characteristics are described in the following lines. ©2010 SPIE'. Source


Raso J.M.,LIDAX | Serrano J.,LIDAX | Argelaguet H.,LIDAX | Lamensans M.,LIDAX | And 7 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

The IACAT (IAC Atmosphere and Telescope) Simulator is an Optical Ground Support Equipment which simulates atmospheric turbulence and reproduces the performance of three very different telescopes: GTC and WHT, located at the Observatorio Del Roque de los Muchachos in La Palma (Canary Islands), and OGS which is located at the Observatorio Del Teide in Tenerife (Canary Islands). Its mission is to provide Scientists with the same measurement conditions as the real telescope but in a friendly laboratory environment, to assist in the development of new adaptive optics methods based on FPGAs. The most important telescope characteristics are simulated, such as f number, pupil size and position, magnification, central obscuration, etc. Up to 13 stellar objects can be created, individually or as binary stars with specific angular separations down to miliarcseconds. For the atmosphere simulation, it allows the creation of three different turbulence layers concurrently with different altitude and wind speed ranges. © 2010 SPIE. Source


Perez-Diaz J.-L.,Charles III University of Madrid | Garcia-Prada J.C.,Charles III University of Madrid | Diez-Jimenez E.,Charles III University of Madrid | Valiente-Blanco I.,Charles III University of Madrid | And 7 more authors.
Mechanism and Machine Theory | Year: 2012

A non-contact linear slider based on stable superconducting magnetic levitation with a long permanent magnet as a slider and two fixed superconducting disks which define the slide way has been designed, built and tested. The slider can be moved stably along a stroke of ± 11.5 mm by supplying a low current in a coil located at the end of the stroke while the levitation remains stable providing a reliable mechanism for linear displacement in a cryogenic environment. The response is linear with a sensitivity of 52 ± 2 μm/mA for displacements lower than 6 mm. Run out, pitch, yaw and roll have been measured demonstrating an overall good performance. In all cases the measured hysteresis was lower than 250 μm and the measured run out was also lower than 250 μm both for Y and Z axis. Roll and yaw were always below 300 μrad, that is one order of magnitude lower than the pitch (4500 μrad). © 2011 Elsevier Ltd All rights reserved. Source

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