Heavy Electrons Observed for First Time

Studying the way in which electrons arrange and interact with each other is an on-going field of research in physics and chemistry. Experts say that knowing more about this could lead to them solving a host of long-standing mysteries in physics. Bringing this objective a little closer were researchers at the US Department of Energy (DOE) Brookhaven National Laboratory (BNL) and Los Alamos National Laboratory (LANL), as well as the McMaster University. For the first time ever, the team managed to capture images of electrons that gain impressive masses in extreme conditions.

These observations are bound to produce far-reaching and long-lasting effects on the physics community, the researchers believe. It would appear that certain extreme conditions make otherwise-normal electrons catch on extraordinary masses, and the new investigation allowed scientists to look at precisely how that happens. The studies, carried out with a microscope designed to image the arrangement and interactions of electrons in crystals, also revealed that an unusual electronic phase transition existed in a class of materials called heavy fermions. Such behavior has been identified in chemical compounds such as rare-Earth and actinide metals.

“Physicists have been interested in the 'problem' of heavy fermions – why these electrons act as if they are hundreds or thousands of times more massive under certain conditions – for thirty or forty years,” explains the reason of the research BNL physicist Seamus Davis, who was the leader of the study. The expert is also the J.D. White Distinguished Professor of Physical Sciences at the Cornell University, in Ithaca, New York. With the new observations method, analyzing the properties and functions of heavy fermions may become easier than ever, researchers from the collaboration believe. Details of the work are published in the June 3 issue of the top-rated scientific journal Nature.

“Heavy fermions remain mysterious in many ways, and it's our job as scientists to solve the problem. This technique reveals that we are dealing with very heavy electrons – or electrons that act as if they are extremely heavy because they are somehow being slowed down. Imagine flying over a body of water where standing waves are moving up and down, but not propagating toward the shore. When you pass over high points, you can touch the water; over low points, you can't. This is similar to what our microscope does. It images how many electrons can jump to the tip of our probe at every point on the surface,” Davies concludes.