Three and a half kilometers beneath the Mediterranean Sea, around 80km off the coast of Sicily, lies half of a very unusual telescope called KM3NeT.
The enormous device is still under construction, but today the telescope’s scientific team announced they have already detected a particle from outer space with a staggering amount of energy.
In fact, as the team report in Nature, they found the most energetic neutrino anyone has ever seen—and it represents a tremendous leap forward in exploring the uncharted waters of the extreme universe.
Researchers have made a breakthrough in THz frequency conversion using graphene.
Graphene is an allotrope of carbon in the form of a single layer of atoms in a two-dimensional hexagonal lattice in which one atom forms each vertex. It is the basic structural element of other allotropes of carbon, including graphite, charcoal, carbon nanotubes, and fullerenes. In proportion to its thickness, it is about 100 times stronger than the strongest steel.
In the grand sweep of scientific history, revolutions in thought are often born from a simple yet unsettling realization: that the fundamental nature of reality is not what we once assumed it to be. In the 20th century, physics was shaken by the twin cataclysms of relativity and quantum mechanics, revealing that space and time themselves were malleable, that particles could exist in superpositions, and that observation played a fundamental role in shaping what we call reality.
Light-sensitive nanoparticles promise a wide range of applications, for example in the field of sensor technology or energy generation. However, these require knowledge and control of the processes taking place within them. Plasmons, collective electron movements in the nanoparticle which transport energy, are essential in the behaviour of such nanoparticles.
Time-resolved experiments in the attosecond range reveal now that the importance of electronic correlations in these plasmons increases when the size of a system decreases to scales of less than one nanometre.
The study, published in the journal Science Advances (“Correlation-driven attosecond photoemission delay in the plasmonic excitation of C 60 fullerene”), was led by the University of Hamburg and DESY as part of a collaboration with Stanford, SLAC National Accelerator Laboratory, Ludwig-Maximilians-Universität München (LMU), Northwest Missouri State University, Politecnico di Milano and the Max Planck Institute for the Structure and Dynamics of Matter (MPSD).
A team of physicists at Fudan University, working with colleagues from Henan University, both in China, and from Nanyang Technological University, in Singapore and Donostia International Physics Center, in Spain, has developed a way to generate topological structures in surface water using gravity water waves. In their study published in Nature, the group used their technique to generate structures such as wave vortices, skyrmions and Möbius strips.
Prior research has shown that various types of waves can be used to achieve desired goals in a variety of applications; optical tweezers, for example, are used to capture and manipulate individual or groups of molecules to create materials or test molecular properties. Sound waves can be used to control much larger particles, or even objects, such as the membrane in a stereo speaker.
For this new study, the research team found a way to generate topological structures on the surface of water by taking advantage of the noise that develops when waves are laid on top of one another, giving them topological properties that can be used to generate wave fields.
A very high-energy muon observed by the KM3NeT experiment in the Mediterranean Sea is evidence for the interaction of an exceptionally high-energy neutrino of cosmic origin.
