Physicists propose new classification of charge density waves

March 10, 2015

LSU Professors in the Department of Physics and Astronomy Ward Plummer and Jiandi Zhang, in collaboration with their colleagues from the Institute of Physics, Beijing, China, have published a paper in the Proceedings of the National Academy of Sciences (Vol. 112, pg. 2367) titled "Classification of Charge Density Waves based on their Nature." This work is a result of a collaboration funded by the Chinese Academy of Sciences.

Charge Density Waves, or CDWs, are observed in many solids, especially in low-dimensional systems. The existence of CDWs was first predicted in the 1930s by Sir Rudolf Peierls, who prophesied that they would exist in an ideal one-dimensional (1-D) chain of atoms, lowering the energy of the system and driving a reconstruction of the lattice. The 1940 paper by Frisch and Peierls described how one could construct an atomic bomb from a small amount of uranium-235. In 1959, Walter Kohn, who received the Nobel Prize in 1998, pointed out that the origin of a CDW in the Peierls' picture would result in what is now known as a "Kohn Anomaly," a simultaneous softening of coherent lattice vibrations, for example, phonon softening. This simple textbook picture of the origin of CDWs does not seem to be correct in most if not all materials.

Therefore, Plummer and Zhang propose a new classification of CDWs based upon their nature.
-end-


Louisiana State University

Related Physics Articles from Brightsurf:

Helium, a little atom for big physics
Helium is the simplest multi-body atom. Its energy levels can be calculated with extremely high precision only relying on a few fundamental physical constants and the quantum electrodynamics (QED) theory.

Hyperbolic metamaterials exhibit 2T physics
According to Igor Smolyaninov of the University of Maryland, ''One of the more unusual applications of metamaterials was a theoretical proposal to construct a physical system that would exhibit two-time physics behavior on small scales.''

Challenges and opportunities for women in physics
Women in the United States hold fewer than 25% of bachelor's degrees, 20% of doctoral degrees and 19% of faculty positions in physics.

Indeterminist physics for an open world
Classical physics is characterized by the equations describing the world.

Leptons help in tracking new physics
Electrons with 'colleagues' -- other leptons - are one of many products of collisions observed in the LHCb experiment at the Large Hadron Collider.

Has physics ever been deterministic?
Researchers from the Austrian Academy of Sciences, the University of Vienna and the University of Geneva, have proposed a new interpretation of classical physics without real numbers.

Twisted physics
A new study in the journal Nature shows that superconductivity in bilayer graphene can be turned on or off with a small voltage change, increasing its usefulness for electronic devices.

Physics vs. asthma
A research team from the MIPT Center for Molecular Mechanisms of Aging and Age-Related Diseases has collaborated with colleagues from the U.S., Canada, France, and Germany to determine the spatial structure of the CysLT1 receptor.

2D topological physics from shaking a 1D wire
Published in Physical Review X, this new study propose a realistic scheme to observe a 'cold-atomic quantum Hall effect.'

Helping physics teachers who don't know physics
A shortage of high school physics teachers has led to teachers with little-to-no training taking over physics classrooms, reports show.

Read More: Physics News and Physics Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.