A team of scientists from different research organizations has conducted a first-of-its-kind direct study on two-dimensional fermion liquids utilizing inelastic neutron scattering technique at the Institut Laue-Langevin (ILL), and identified a new class of very-short wave-length density wave in these liquids.
Fermi liquids contain fermion particles, which are a group of strongly interacting particles such as neutrons, protons, electrons and quarks. They are one among the two quantum liquid types utilized to simulate and elucidate the complicated interplay between atoms or sub-atomic particles.
The team consists of scientists from the Johannes Kepler University in Austria, SUNY University at Buffalo and Oak Ridge National Laboratory in the United States, Aalto University in Finland (Microkelvin Collaboration), and Institut Néel (Centre national de la recherche scientifique and Université J. Fourier) in France. The study findings, reported in Nature, will be useful to scientists investigating electronic systems as this kind of density fluctuations may cause high temperature superconductivity.
In the study, the research team focused the neutrons on a one-atom-thick helium-3 layer, which behaves like a Fermi liquid at temperatures nearing absolute zero. The neutron scattering technique allowed the research team to discover very short wave-length, high-frequency density waves called as zero-sound oscillations. The study results showed the strong existence of zero sound modes in the two-dimensional fermion liquids when compared to earlier ILL studies on bulk liquids, where these modes were strongly suppressed.
After completing the study of the helium system properties, the research team’s next step is to apply this perceptive to electron liquids. Dr. Henri Godfrin, who serves as Director of research at CNRS at the Institut Néel, informed that this discovery is important in the quantum fluid field, which has direct effects in other fields of many-body physics, especially in understanding the physics behind neutron stars and the fabrication of metals.
Source: http://www.ill.eu