Credit: Tohoku University
Using the circular vibration of surface acoustic waves, a collaborative research group have successfully controlled the magnetization of a ferromagnetic thin film.
Their research was published in the journal
Nature Communications on May 10, 2021.
Essentially, acoustic waves are waves of atomic vibrations in a substance. When the waves propagate across the surface of a material, the vibration becomes circular. This circular motion, known as angular momentum, can help measure rotational motion.
Surface acoustic waves are utilized in bandpass filters in cell phones. The bandpass allows certain frequencies in and keeps unneeded frequencies out. However, storage devices in computers are composed of ferromagnets.
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IMAGE: Two mirrors with a drop of oil in between form a non-linear optical cavity, in which stochastic resonance was observed. By modulating the position on one of the mirrors,. view more
Credit: AMOLF Interacting Photons group
Signals can be amplified by an optimum amount of noise, but this so-called stochastic resonance is a rather fragile phenomenon. Researchers at AMOLF were the first to investigate the role of memory for this phenomenon in an oil-filled optical microcavity. The effects of slow non-linearity (i.e. memory) on stochastic resonance were never considered before, but these experiments suggest that stochastic resonance becomes robust to variations in the signal frequency when systems have memory. This has implications in many fields of physics and energy technology. In particular, the scientists numerically show that introducing slow non-linearity in a mechanical oscillator harvesting energy from noise can increase its efficiency by tenfold. The
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IMAGE: A large number of candidate materials are chosen from experimental or computational databases, and a sequence of screening calculations reduces their number down to a small set of candidates with. view more
Credit: @Nicola Marzari
Over the past 20 years, first-principles simulations have become powerful, widely used tools in many, diverse fields of science and engineering. From nanotechnology to planetary science, from metallurgy to quantum materials, they have accelerated the identification, characterization, and optimization of materials enormously. They have led to astonishing predictions from ultrafast thermal transport to electron-phonon mediated superconductivity in hydrides to the emergence of flat bands in twisted-bilayer graphene that have gone on to inspire remarkable experiments.
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IMAGE: A fluorescent microscope image of a thin section of a human kidney stone reveals a complex history of crystal growth layering, fracturing, dissolution and recrystallization. view more
Credit: Image courtesy of Mayandi Sivaguru, University of Illinois
CHAMPAIGN, Ill. Advanced microscope technology and cutting-edge geological science are giving new perspectives to an old medical mystery: How do kidney stones form, why are some people more susceptible to them and can they be prevented?
In a new paper published in the journal
Nature Reviews Urology, researchers from the University of Illinois Urbana-Champaign, Mayo Clinic and other collaborators described the geological nature of kidney stones, outlined the arc of their formation, established a new classification scheme and suggested possible clinical interventions.