Category Physics

Scientists have proposed a graphene-based sensor that can ‘sniff out’ a single molecule of explosives. Credit: Graphene-based sensor

A graphene-based spaser can detect even small amounts of various substances, including explosives, toxic chemicals, and other organic compounds based on a single molecule. Scientists have long been fascinated by the potential applications of a quasiparticle called the plasmon, a quantum of plasma oscillations. In the case of a solid body, plasmons are the oscillations of free electrons.

Of special interest are the effects from the surface interactions of electromagnetic waves with plasmons – usually in the context of metals or semimetals, as they have a higher free electron density...

Magnetic perturbations in a fusion plasma are shown. Credit: Gerrit Kramer

Physicists led by Gerrit Kramer at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have conducted simulations that suggest that applying magnetic fields to fusion plasmas can control instabilities known as Alfvén waves that can reduce the efficiency of fusion reactions. Such instabilities can cause quickly moving charged particles called “fast ions” to escape from the core of the plasma, which is corralled within machines known as tokamaks. Controlling these instabilities leads to higher temperatures within tokamaks and thus more efficient fusion processes.

“Controlling and suppressing the instabilities helps improve the fast-ion confinement and plasma performance,” said Kramer, a r...

A new class of gas-fired heat pump water heaters, based on a novel semi-open sorption concept, could replace the evaporator in a traditional devices with a vapor-permeable membrane that more efficiently absorbs and transfers heat for residential applications. Credit: ORNL

Scientists from Dept of Energy’s Oak Ridge National Laboratory and the University of Florida has developed a novel method that could yield lower-cost, higher-efficiency systems for water heating in residential buildings. The theory behind the newly termed “semi-open” natural gas-fired design reduces the cost and complexity of traditional closed gas-fired systems by streamlining, and even eliminating, certain components.

“When applied, the new concept could result in better than 100% energy efficiency, because the system d...

Physicists at the Institute for Nuclear Research in Debrecen, Hungary, say this apparatus — an electron-positron spectrometer — has found evidence for a new particle.

Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature. “If true, it’s revolutionary,” said Prof. Jonathan Feng. “For decades, we’ve known of 4 fundamental forces: gravitation, electromagnetism, and the strong and weak nuclear forces. If confirmed by further experiments, this discovery of a possible fifth force would completely change our understanding of the universe, with consequences for the unification of forces and dark matter.”

The UCI researchers came upon a mid-2015 study by experimental nuclear physicists at the Hungarian...