Ultralow‐Power Atomic‐Scale Tin Transistor with Gate Potential in Millivolt

After decades of continuous scaling, further advancement of complementary metal-oxide-semiconductor (CMOS) technology across the entire spectrum of computing applications is today limited by power dissipation, which scales with the square of the supply voltage. Here, an atomic-scale tin transistor is demonstrated to perform conductive switching between bistable configurations with on/off potentials ≤2.5 mV in magnitude. In addition to the low operation voltage, the channel length of the transistor is determined experimentally and with density-functional theory to be ≤1 nm because the atoms instead of electrons are information carriers in this device. The conductance at on-states of the bistable configurations varies between 1.2 G$_{0}$ to 197 G$_{0}$ (G$_{0}$ = 2e$^{2}$ h$^{-1}$, e stands for the electron charge and h for Planck\u27s constant). Thus, the device can supply driving current from 1 to ≈375 µA in magnitude for logic circuits with the drain-source dc voltage at decades of millivolts. The switching frequency of the atomic-scale tin transistor has reached 2047 Hz. Furthermore, the on/off potentials in millivolts can reduce the energy consumption in the interconnects of integrated circuits at least by ≈400 times. Therefore, the atomic-scale tin transistor has prospects in digital circuits with ultralow-power dissipation and can contribute to the sustainability of modern society

The diagnostic path, a useful visualisation tool in virtual microscopy

BACKGROUND: The Virtual Microscopy based on completely digitalised histological slide. Concerning this digitalisation many new features in mircoscopy can be processed by the computer. New applications are possible or old, well known techniques of image analyses can be adapted for routine use. AIMS: A so called diagnostic path observes in the way of a professional sees through a histological virtual slide combined with the text information of the dictation process. This feature can be used for image retrieval, quality assurance or for educational purpose. MATERIALS AND METHODS: The diagnostic path implements a metadata structure of image information. It stores and processes the different images seen by a pathologist during his "slide viewing" and the obtained image sequence ("observation path"). Contemporary, the structural details of the pathology reports were analysed. The results were transferred into an XML structure. Based on this structure, a report editor and a search function were implemented. The report editor compiles the "diagnostic path", which is the connection from the image viewing sequence ("observation path") and the oral report sequence of the findings ("dictation path"). The time set ups of speech and image viewing serve for the link between the two sequences. The search tool uses the obtained diagnostic path. It allows the user to search for particular histological hallmarks in pathology reports and in the corresponding images. RESULTS: The new algorithm was tested on 50 pathology reports and 74 attached histological images. The creation of a new individual diagnostic path is automatically performed during the routine diagnostic process. The test prototype experienced an insignificant prolongation of the diagnosis procedure (oral case description and stated diagnosis by the pathologist) and a fast and reliable retrieval, especially useful for continuous education and quality control of case description and diagnostic work. DISCUSSION: The Digital Virtual Microscope has been designed to handle 1000 images per day in the daily routine work of a pathology institution. It implies the necessity of an automatic mechanism of image meta dating. The non – deterministic correlation between the oral statements (case report) and image information content guides the image meta dating. The presented software opens up new possibilities for a content oriented search in a virtual slide, and can successfully support medical education and diagnostic quality assurance

Bioäpfel - besser und gesünder? Eine Vergleichsstudie mit Standard- und Alternativmethoden der Qualitätserfassung

Die am FiBL auf drei Jahre angelegte Vergleichsstudie für Äpfel aus integrierter und biologischer Produktion weist nach dem ersten Versuchsjahr signifikante anbaubedingte Unterschiede nach

Direct digital control of an efficient silicon+lequid crystal phase shifter

We demonstrate a phase shifter based on a silicon slot waveguide infiltrated with liquid crystal. We achieve a phase shift of 73 pi for a 5V drive voltage, with a voltage-length product of 0.022V.mm around 1V. We can drive the phase shifter directly with a 1V, duobinary pulse-width-modulated signal, allowing direct digital CMOS control of an analog optical phase shifter

Optical properties of highly nonlinear silicon-organic hybrid (SOH) waveguide geometries

Geometry, nonlinearity, dispersion and two-photon absorption figure of merit of three basic silicon-organic hybrid waveguide designs are compared. Four-wave mixing and heterodyne pump-probe measurements show that all designs achieve high nonlinearities. The fundamental limitation of two-photon absorption in silicon is overcome using silicon-organic hybrid integration, with a five-fold improvement for the figure of merit (FOM). The value of FOM = 2.19 measured for silicon-compatible nonlinear slot waveguides is the highest value published. (C) 2009 Optical Society of Americ

Controlling Volatility and Nonvolatility of Memristive Devices by Sn Alloying

Memristive devices have attracted significant attention due to their downscaling potential, low power operation, and fast switching performance. Their inherent properties make them suitable for emerging applications such as neuromorphic computing, in-memory computing, and reservoir computing. However, the different applications demand either volatile or nonvolatile operation. In this study, we demonstrate how compliance current and specific material choices can be used to control the volatility and nonvolatility of memristive devices. Especially, by mixing different materials in the active electrode, we gain additional design parameters that allow us to tune the devices for different applications. We found that alloying Ag with Sn stabilizes the nonvolatile retention regime in a reproducible manner. Additionally, our alloying approach improves the reliability, endurance, and uniformity of the devices. We attribute these advances to stabilization of the filament inside the switching medium by the inclusion of Sn in the filament structure. These advantageous properties of alloying were found by investigating a choice of six electrode materials (Ag, Cu, AgCu-1, AgCu-2, AgSn-1, AgSn-2) and three switching layers (SiO$_2$, Al$_2$O$_3$, HfO$_2$)

40 GHz small-signal cross-gain modulation in 1.3m quantum dot semiconductor optical amplifiers

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 93, 051110 (2008) and may be found at https://doi.org/10.1063/1.2969060.Small-signal cross-gain modulation of quantum dot based semiconductor optical amplifiers (QD SOAs), having a dot-in-a-well structure, is presented, demonstrating superiority for ultrahigh bit rate wavelength conversion. Optimization of the QD SOA high speed characteristics via bias current and optical pump power is presented and a small-signal 3 dB bandwidth exceeding 40 GHz is demonstrated. The -doped samples investigated here enable small-signal wavelength conversion within a range of 30 nm, limited mainly by the gain bandwidth.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, BauelementeEC/FP6/027638/EU/Transparent Ring Interconnection Using Multiwavelngth PHotonic switches/TRIUMPHEC/FP6/500101/EU/Self-Assembled semiconductor Nanostructures for new Devices in photonics and Electronics/SANDI

Operations of and Future Plans for the Pierre Auger Observatory

Technical reports on operations and features of the Pierre Auger Observatory, including ongoing and planned enhancements and the status of the future northern hemisphere portion of the Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009.Comment: Contributions to the 31st ICRC, Lodz, Poland, July 200