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Freer EM, Grachev O, Duan X, Martin S, Stumbo DP. High-yield self-limiting single-nanowire assembly with dielectrophoresis. Nat Nanotech. 2010;5(7):525–530.
Abstract: Single-crystal nanowire transistors and other nanowire-based devices could have applications in large-area and flexible electronics if conventional top-down fabrication techniques can be integrated with high-precision bottom-up nanowire assembly. Here, we extend dielectrophoretic nanowire assembly to achieve a 98.5% yield of single nanowires assembled over 16,000 patterned electrode sites with submicrometre alignment precision. The balancing of surface, hydrodynamic and dielectrophoretic forces makes the self-assembly process controllable, and a hydrodynamic force component makes it self-limiting. Our approach represents a methodology to quantify nanowire assembly, and makes single nanowire assembly possible over an area limited only by the ability to reproduce process conditions uniformly.
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Konstantatos G, Sargent EH. Nanostructured materials for photon detection. Nat Nanotech. 2010;5(6):391–400.
Abstract: The detection of photons underpins imaging, spectroscopy, fibre-optic communications and time-gated distance measurements. Nanostructured materials are attractive for detection applications because they can be integrated with conventional silicon electronics and flexible, large-area substrates, and can be processed from the solution phase using established techniques such as spin casting, spray coating and layer-by-layer deposition. In addition, their performance has improved rapidly in recent years. Here we review progress in light sensing using nanostructured materials, focusing on solution-processed materials such as colloidal quantum dots and metal nanoparticles. These devices exhibit phenomena such as absorption of ultraviolet light, plasmonic enhancement of absorption, size-based spectral tuning, multiexciton generation, and charge carrier storage in surface and interface traps.
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Stevens MJ, Baek B, Dauler EA, Kerman AJ, Molnar RJ, Hamilton SA, et al. High-order temporal coherences of
chaotic and laser light. Opt Express. 2010;18(2):1430–7.
Abstract: We demonstrate a new approach to measuring high-order temporal coherences that uses a four-element superconducting nanowire single-photon detector. The four independent, interleaved single-photon-sensitive elements parse a single spatial mode of an optical beam over dimensions smaller than the minimum diffraction-limited spot size. Integrating this device with four-channel time-tagging electronics to generate multi-start, multi-stop histograms enables measurement of temporal coherences up to fourth order for a continuous range of all associated time delays. We observe high-order photon bunching from a chaotic, pseudo-thermal light source, measuring maximum third- and fourth-order coherence values of 5.87 ± 0.17 and 23.1 ± 1.8, respectively, in agreement with the theoretically predicted values of 3! = 6 and 4! = 24. Laser light, by contrast, is confirmed to have coherence values of approximately 1 for second, third and fourth orders at all time delays.
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Zhong T, Hu X, Wong FNC, Berggren KK, Roberts TD, Battle P. High-quality fiber-optic polarization entanglement distribution at 1.3 μm telecom wavelength. Opt Lett. 2010;35(9):1392–4.
Abstract: We demonstrate high-quality distribution of 1.3 μm polarization-entangled photons generated from a fiber-coupled periodically poled KTiOPO4 waveguide over 200 m fiber-optic cables. Time-multiplexed measurements with a 19% efficient superconducting nanowire single-photon detector at the remote location show a detected flux of 5.8 pairs / s at a pump power of 25 μW and an average two-photon quantum-interference visibility of 97.7% without subtraction of accidentals.
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Mannino G, Spinella C, Ruggeri R, La Magna A, Fisicaro G, Fazio E, et al. Crystallization of implanted amorphous silicon during millisecond annealing by infrared laser irradiation. Appl Phys Lett. 2010;97(2):3.
Abstract: We investigated the homogenous nucleation of crystalline grains in amorphous Si during transient temperature pulse of few milliseconds IR laser irradiation. The crystallized volume fraction is ~80%. Significant crystallization occurs in nonsteady regime because of the rapid temperature variation (106 °C/s). Our model combines the time evolution of the crystal grain population with the consumption of the amorphous volume due to the growth of grains. Thanks to the experimental approach based on a laser source to heat α-Si and the theoretical model we extended the description of the spontaneous crystallization up to 1323 K or 250 K above the temperature investigated by conventional annealing.
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Jang YR, Yoo K-H, Park SM. Rapid thermal annealing of ZnO thin films grown at room temperature. J. Vac. Sci. Technol. A. 2010;28(2):4.
Abstract: The authors successfully obtained high quality ZnO thin films by growing them at room temperature (RT) and postannealing by rapid thermal annealing (RTA). The thin films were grown by pulsed laser deposition on Si (100) substrates at RT, and RTA was performed under various temperatures and ambient conditions. Based on the UV emission to visible emission ratio in RT photoluminescence (PL) spectra, the optimum film was obtained at annealing temperature ~700 °C in an ambient of Ar, N2, or O2 at 0.1 Torr, while the optimum annealing temperature was above 1100 °C in the air ambient at atmospheric pressure. The morphology and structure of the films in different RTA conditions were investigated by using field emission scanning electron microscopy and grazing incidence x-ray diffraction, and were discussed in conjunction with the PL data.
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Poglitsch A, Waelkens C, Geis N, Feuchtgruber H, Vandenbussche B, Rodriguez L, et al. The Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory. A&A. 2010;518:12.
Abstract: The Photodetector Array Camera and Spectrometer (PACS) is one of the three science instruments on ESA's far infrared and submillimetre observatory. It employs two Ge:Ga photoconductor arrays (stressed and unstressed) with 16×25 pixels, each, and two filled silicon bolometer arrays with 16×32 and 32×64 pixels, respectively, to perform integral-field spectroscopy and imaging photometry in the 60-210 μm wavelength regime. In photometry mode, it simultaneously images two bands, 60-85 μm or 85-125 μm and 125-210 μm, over a field of view of ~1.75'× 3.5', with close to Nyquist beam sampling in each band. In spectroscopy mode, it images a field of 47â€ × 47â€, resolved into 5×5 pixels, with an instantaneous spectral coverage of ~1500 km s-1 and a spectral resolution of ~175 km s-1. We summarise the design of the instrument, describe observing modes, calibration, and data analysis methods, and present our current assessment of the in-orbit performance of the instrument based on the performance verification tests. PACS is fully operational, and the achieved performance is close to or better than the pre-launch predictions.
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Griffin MJ, Abergel A, Abreu A, Ade PAR, André P, Augueres J-L, et al. The Herschel-SPIRE instrument and its in-flight performance. A&A. 2010;518:7.
Abstract: The Spectral and Photometric Imaging REceiver (SPIRE), is the Herschel Space Observatory`s submillimetre camera and spectrometer. It contains a three-band imaging photometer operating at 250, 350 and 500 μm, and an imaging Fourier-transform spectrometer (FTS) which covers simultaneously its whole operating range of 194-671 μm (447-1550 GHz). The SPIRE detectors are arrays of feedhorn-coupled bolometers cooled to 0.3 K. The photometer has a field of view of 4Â´× 8´, observed simultaneously in the three spectral bands. Its main operating mode is scan-mapping, whereby the field of view is scanned across the sky to achieve full spatial sampling and to cover large areas if desired. The spectrometer has an approximately circular field of view with a diameter of 2.6´. The spectral resolution can be adjusted between 1.2 and 25 GHz by changing the stroke length of the FTS scan mirror. Its main operating mode involves a fixed telescope pointing with multiple scans of the FTS mirror to acquire spectral data. For extended source measurements, multiple position offsets are implemented by means of an internal beam steering mirror to achieve the desired spatial sampling and by rastering of the telescope pointing to map areas larger than the field of view. The SPIRE instrument consists of a cold focal plane unit located inside the Herschel cryostat and warm electronics units, located on the spacecraft Service Module, for instrument control and data handling. Science data are transmitted to Earth with no on-board data compression, and processed by automatic pipelines to produce calibrated science products. The in-flight performance of the instrument matches or exceeds predictions based on pre-launch testing and modelling: the photometer sensitivity is comparable to or slightly better than estimated pre-launch, and the spectrometer sensitivity is also better by a factor of 1.5-2.
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Schwarz B. Lidar: Mapping the world in 3D. Nat Photon. 2010;4(7):429–30.
Abstract: A high-definition LIDAR system with a rotating sensor head containing 64 semiconductor lasers allows the efficient generation of 3D environment maps at unprecedented levels of detail.
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Третьяков ИВ, Рябчун СА, Каурова НС, Ларионов ПА, Лобастова АА, Воронов БМ, et al. Оптимальная поглощенная мощность гетеродина для терагерцового сверхпроводникового NbN смесителя на электронном разогреве. Письма в ЖТФ. 2010;36(23):78–84.
Abstract: Представлены результаты измерений поглощенной мощности гетеродина малошумящим широкополосным смесителем на эффекте электронного разогрева в резистивном состоянии сверхпроводниковой ультратонкой пленки NbN. Оптимальная поглощенная мощность гетеродина составила около 100 nW на частоте 2.5 THz.
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