Since their discovery in 1991, carbon nanotubes have continually fascinated physicists and chemists with their amazing electronic and mechanical properties.
These cylindrical molecules with a radius of a few Angstroms (1×10-10 meters) and with lengths of up to several micrometers (1×10-6 meters) have endless applications inside different scientific fields from nanoelectronics to material science, and are used by scientists to study a wide range of physical phenomena that only take place at a nanometric scale.
The combination of nanotubes and other materials form hybrid structures and these are of particular interest. For example, carbon nanotubes connected to superconductive electrodes (materials that offer no electrical resistance at low temperatures) are currently being used to study exotic physical phenomena like the Josephson Effect. This Nobel Prize winning discovery made by physicist Brian D. Josephson in 1973 consists of the almost magic effect of producing an electrical current in a superconductive junction without the application of a voltage.
In the last two three years several research groups have demonstrated that in a carbon nanotube held in between superconducting electrodes, the Josephson effect can be controlled at will, making possible a superconductive version of a transistor. This discovery has endless possibilities, most of which have barely started to be investigated.
A research group from the UAM working in collaboration with a research team lead by Christian Schoenenberger of Basilea University, has recently published an article in the Physical Review Letters, where a new phenomenon that takes place within these nanotube-superconductor structures has been described.
Demonstrating that carbon nanotubes truly are an endless supply of new physical phenomena, they have discovered that when a voltage is applied to these hybrid structures, the electric current that flows depends greatly on the number of electrons that are present at the nanotube, and furthermore, whether this number is even or odd has a drastic impact. This new transport phenomenon is caused by subtle interactions between the Spins (magnetic field produced by the electrons as they rotate) of the electrons in the carbon nanotubes - a characteristic which depends on their number and the conducting electrons in the superconductor.
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Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
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For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
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