One of the hallmarks of quantum mechanics -- the laws of physics that apply on very small scales -- is the wave nature exhibited by sub-atomic particles such as electrons. An electron presented with two paths to a destination will use its wave nature to traverse both paths and, depending on the parameters of the two paths, will constructively or destructively interfere with itself at its destination, leading to a high or low probability of it appearing there.
A classic demonstration of this is the Aharonov-Bohm effect where electrons are sent along two paths that may be altered by the application of an external magnetic field. By tuning the magnetic field, the constructive or destructive interference of the electrons is manifested as an increase or decrease in the conduction of electric current. Now physicists at Northwestern University show that, using the fact that electrons carry heat as well as charge, the conduction of heat may be similarly tuned. Their findings will be published April 22 by Physical Review Letters, the journal of the American Physical Society.
Venkat Chandrasekhar, professor of physics in Northwesterns Weinberg College of Arts and Sciences, and his graduate student Zhigang Jiang showed that a magnetic field can be used to increase or decrease the flow of heat through an "Andreev interferometer," a nanoscale device with one normal metal path and one superconducting path. Though the quantum interference of electrons in this device is responsible for these changes in heat flow, the flow of charge through the interferometer is zero. The researchers recently observed this effect experimentally.
Megan Fellman | EurekAlert!
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Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
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An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
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In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
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