This study explored spatiotemporal progression patterns of striatal dopamine availability and regional brain volume based on cognitive status among patients with Parkinson disease:
Background and Objectives.
This study explored spatiotemporal progression patterns of striatal dopamine availability and regional brain volume based on cognitive status among patients with Parkinson disease:
Background and Objectives.
Researchers have measured a hard-to-observe electronic transition in strontium that was predicted six decades ago.
Spintronics relies on the transport of spin currents for computing and communication applications. New device designs would be possible if this spin transport could be carried out by both electrons and magnetic waves called magnons. But spin transport via magnons typically requires electrically insulating magnets—materials that cannot be easily integrated with silicon electronics. A way to bypass that requirement has now been found by Matthias Althammer at the Bavarian Academy of Sciences and Humanities in Germany and his colleagues [1]. The researchers say that this finding could have important implications for both spintronic applications and fundamental research on spin transport.
To demonstrate their concept, Althammer and his colleagues placed two magnetic, metallic strips—each hosting coupled electrons and magnons—on a nonmagnetic, insulating substrate. In the first strip, the researchers converted electron charge currents to electron spin currents. These spin currents were transferred first to the magnons in the same strip, then across the substrate to the magnons in the second strip, and finally to the electrons in the second strip. The researchers detected this spin transport by converting the electron spin currents in the second strip to charge currents.
Althammer and his colleagues studied how the spin transport between the two strips depended on temperature and strip separation. These measurements suggested that the transport was achieved via a magnetic dipole–dipole interaction between the strips. But the researchers could not rule out the possibility that it partly or mainly occurred via crystal vibrations in the substrate. Solving this open problem, which the researchers plan to do in upcoming work, will help in optimizing devices based on this principle.
A team of international scientists led by the University of Ottawa have gone back to the kitchen cupboard to create a recipe that combines organic material and light to create quantum states.
Scientists on the hunt for compact and robust sources of multicolored laser light have generated the first topological frequency comb. Their result, which relies on a small silicon nitride chip patterned with hundreds of microscopic rings, appears in the journal Science.
A new study published in Physical Review Letters (PRL) explores the potential of quadratic electron-phonon coupling to enhance superconductivity through the formation of quantum bipolarons.
The quantum internet would be a lot easier to build if we could use existing telecommunications technologies and infrastructure. Over the past few years, researchers have discovered defects in silicon—a ubiquitous semiconductor material—that could be used to send and store quantum information over widely used telecommunications wavelengths. Could these defects in silicon be the best choice among all the promising candidates to host qubits for quantum communications?
The human eye can only see light at certain frequencies (called the visible spectrum), the lowest of which constitutes red light. Infrared light, which we can’t see, has an even lower frequency than red light. Researchers at the Indian Institute of Science (IISc) have now fabricated a device to increase or “up-convert” the frequency of short infrared light to the visible range.
A joint research team that included members from Tohoku University has unveiled a new topological insulator (TI), a unique state of matter that differs from conventional metals, insulators, and semiconductors.
Terahertz waves are being intensely studied by researchers around the world seeking to understand the “terahertz gap.” Terahertz waves have a specific frequency that puts them somewhere between microwaves and infrared light. This range is referred to as a “gap” because much remains unknown about these waves.