Gallium is a chemical element with symbol Ga and atomic number 31. Elemental gallium does not occur as a free element in nature, but as gallium(III) compounds in trace amounts in zinc ores and in bauxite. Elemental gallium is a soft, silvery metal at standard temperature and pressure, a brittle solid at low temperatures, and a liquid at temperatures greater than 29.76 °C (85.57 °F) (slightly above room temperature). The melting point of gallium is used as a temperature reference point. The alloy galinstan (68.5% gallium, 21.5% indium, and 10% tin) has an even lower melting point of −19 °C (−2 °F), well below the freezing point of water.

  • 30.2 Percent Efficiency – New Record for Silicon-based Multi-junction Solar Cell

    Wafer-bonded III-V / Si multi-junction solar cell with 30.2 percent efficiency. ©Fraunhofer ISE/A. Wekkeli

    Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with the Austrian company EV Group (EVG) have successfully manufactured a silicon-based multi-junction solar cell with two contacts and an efficiency exceeding the theoretical limit of silicon solar cells. For this achievement, the researchers used a “direct wafer bonding” process to transfer a few micrometers of III-V semiconductor material to silicon, a well-known process in the microelectronics industry. After plasma activation, the subcell surfaces are bonded together in vacuum by applying pressure. The atoms on the surface of the III-V subcell form bonds with the silicon atoms, creating a monolithic device.

  • Annual Production of Gallium and Germanium could be much higher | Bernd Rendel Prize 2016

    Der Geowissenschaftler Max Frenzel ist einer von zwei Preisträgern des diesjährigen Bernd Rendel-Preises für Geowissenschaften 2016 der Deutschen Forschungsgemeinschaft.   HZDR

    The global supply potential of the high-tech metals gallium and germanium is much greater than actual annual production levels. This is the main conclusion from Max Frenzel’s work. Frenzel, a postgraduate student at the Helmholtz Institute Freiberg for Resource Technology (HIF), which closely cooperates with the TU Bergakademie Freiberg, is one of two recipients of the Bernd Rendel Prize for Geosciences 2016. The prize, awarded by the German Research Foundation (DFG), will be presented on 28th September at the annual conference of the German Geological Society (DGGV) in Innsbruck.

  • Coupling a Nano-trumpet With a Quantum Dot Enables Precise Position Determination

    Trumpet-shaped nanowires with a length of about 10 micrometers are coupled to quantum dots located at their bases. Grenoble Alps University

    Scientists from the Swiss Nanoscience Institute and the University of Basel have succeeded in coupling an extremely small quantum dot with 1,000 times larger trumpet-shaped nanowire. The movement of the nanowire can be detected with a sensitivity of 100 femtometers via the wavelength of the light emitted by the quantum dot. Conversely, the oscillation of the nanowire can be influenced by excitation of the quantum dot with a laser. Nature Communications published the results.

  • Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

    New materials enable high speed frequencies: Fraunhofer ISE develops resonant DC/DC converters with 2.5 MHz as demonstrator for aeronautical applications. ©Fraunhofer ISE

    The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

  • Novel Topological Insulator

    The novel topological insulator built in the Würzburg Institute of Physics: a controllable flow of hybrid optoelectronic particles (red) travels along its edges. (Picture: Karol Winkler)

    For the first time, physicists have built a unique topological insulator in which optical and electronic excitations hybridize and flow together. They report their discovery in "Nature". Topological insulators are materials with very special properties. They conduct electricity or light particles on their surface or edges only but not on the inside. This unusual behaviour could eventually lead to technical innovations which is why topological insulators have been the subject of intense global research for several years.

  • Supported Liquid Metal Catalysts – a New Generation of Reaction Accelerators

    A diagram illustrating the processes at the catalytic surface of a liquid drop of gallium containing small amounts of palladium during the catalytic dehydrogenation of n-butane.  Image: FAU/Mathias Grabau and Florian Maier

    Catalysts are agents that initiate chemical reactions, speed them up or significantly increase the yield of the desired product. New and improved catalysts are thus considered the key to creating more sustainable and efficient production processes in the chemical industry. In a joint research project, five professors at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) and their teams have recently discovered how to bypass the known drawbacks of the technical catalysts that are currently in use by means of a new material concept that makes the creation of significantly more efficient catalysts possible.