The pulse of an atom’s magnetic heart as it ticks back and forth between quantum states has been timed in a laboratory.
Physicists used a scanning tunneling microscope to observe electrons as they moved in sync with the nucleus of an atom of titanium-49, allowing them to estimate the duration of the core’s magnetic beat in isolation.
“These findings,” they write in their paper, “give an atomic-scale insight into the nature of nuclear spin relaxation and are relevant for the development of atomically assembled qubit platforms.”
At any given moment, trillions of particles called neutrinos are streaming through our bodies and every material in our surroundings, without noticeable effect. Smaller than electrons and lighter than photons, these ghostly entities are the most abundant particles with mass in the universe.
The exact mass of a neutrino is a big unknown. The particle is so small, and interacts so rarely with matter, that it is incredibly difficult to measure. Scientists attempt to do so by harnessing nuclear reactors and massive particle accelerators to generate unstable atoms, which then decay into various byproducts including neutrinos. In this way, physicists can manufacture beams of neutrinos that they can probe for properties including the particle’s mass.
Now MIT physicists propose a much more compact and efficient way to generate neutrinos that could be realized in a tabletop experiment.
Imagine a clock that doesn’t have electricity, but its hands and gears spin on their own for all eternity. In a new study, physicists at the University of Colorado Boulder have used liquid crystals, the same materials that are in your phone display, to create such a clock—or, at least, as close as humans can get to that idea. The team’s advancement is a new example of a “time crystal.” That’s the name for a curious phase of matter in which the pieces, such as atoms or other particles, exist in constant motion.
The researchers aren’t the first to make a time crystal, but their creation is the first that humans can actually see, which could open a host of technological applications.
“They can be observed directly under a microscope and even, under special conditions, by the naked eye,” said Hanqing Zhao, lead author of the study and a graduate student in the Department of Physics at CU Boulder.
Seventy years ago, in Osmond Laboratory on Penn State’s University Park campus, Erwin W. Müller, Evan Pugh Research Professor of Physics, became the first person to “see” an atom. In doing so, Müller cemented his legacy, not only at Penn State, but also as a pioneer in the world of physics and beyond.
Graphene is an extraordinary material—a sheet of interlocking carbon atoms just one atom thick that is stable and extremely conductive. This makes it useful in a range of areas, such as flexible electronic displays, highly precise sensors, powerful batteries, and efficient solar cells.
A new study—led by researchers from the University of Göttingen, working together with colleagues from Braunschweig and Bremen in Germany, and Fribourg in Switzerland—now takes graphene’s potential to a whole new level. The team has directly observed “Floquet effects” in graphene for the first time.
This resolves a long-standing debate: Floquet engineering—a method in which the properties of a material are very precisely altered using pulses of light—also works in metallic and semi-metallic quantum materials such as graphene. The study is published in Nature Physics.
Spintronics, or spin-electronics, is a revolutionary approach to information processing that utilizes the intrinsic angular momentum (spin) of electrons, rather than solely relying on electric charge flow. This technology promises faster, more energy-efficient data storage and logic devices. A central challenge in fully realizing spintronics has been the development of materials that can precisely control electron spin direction.
In a new development for spin-nanotechnology, researchers led by Professor Young Keun Kim of Korea University and Professor Ki Tae Nam of Seoul National University have successfully created magnetic nanohelices that can control electron spin.
This technology, which utilizes chiral magnetic materials to regulate electron spin at room temperature, has been published in Science.
A new and powerful particle detector just passed a critical test in its goal to decipher the ingredients of the early universe. The sPHENIX detector is the newest experiment at Brookhaven National Laboratory’s Relativistic Heavy Ion Collider (RHIC) and is designed to precisely measure products of high-speed particle collisions.