Nav: Home

MSU-based physicists studied complex magnetism in a rare earth compound

July 30, 2018

DyGe3 or dysprosium germanide is a silver-white rare earth element that is not very often found in the Earth crust. It forms refractory oxides that are almost insoluble in water. During the study the scientists applied the pressure of 8 GPa to obtain polycrystal samples of dysprosium germanide in a metastable state state of local thermodynamic equilibrium capable of changing to a more stable state under certain conditions.

The physicists found a charge-density wave (CDW) in this compound - the phenomenon which occurs in some crystals at low temperatures due to the peculiarities of their electron structure. A CDW describes space-periodic modulations of ions and electron density, i.e. the oscillating space probability of finding electrons and ions along the CDW propagation.

Recent studies paid much attention to the physics of CDW in rare earth compounds and how this wave influences crystal lattice distortions and magnetic ordering. Magnetic ordering implies a spontaneous alignment of vectors of atomic magnetic moments in a substance. These vectors located at atom positions can point out in different directions: they can be either parallel (ferromagnetic order) or anti-parallel (anti-ferromagnetic order) to each other. A few years ago scientists found out that a CDW can precede and co-exist with the anti-ferromagnetic order.

When the temperature is lowered, CDW appears in the dysprosium germanide, followed by a transition to an anti-ferromagnetic order at still lower temperature.

"We've discovered that when the crystal lattice structure is slightly distorted, the local crystal site symmetry around certain atoms changes, and the substance experiences a transition to CDW. The wave influences magnetic properties of the material, causing the appearance of a spiral magnetic structure," - pointed out Alexander Nikolaev, a co-author of the article, Doctor of Physical and Mathematical Sciences, lead researcher at the laboratory of electron-nuclear and molecular processes of SINP.

According to the team, the obtained results help to understand better the mechanisms of correlations between charge and spin characteristics of electron system. The former ones are associated with CDW, and the latter - with the anti-ferromagnetic order.

"Our work focuses mostly on fundamental issues of condensed-matter physics, which include magnetism and structural phase transition. In the future this work can lead to a better understanding of complex magnetism in rare earth elements and the appearance of new prospective materials," - concluded the scientist.
-end-
The work was carried out in close collaboration with scientists from the Institute for High Pressure Physics (RAS), Moscow Institute of Physics and Technology and Joint Institute for Nuclear Research, Institute for Nuclear Studies and Nuclear Energy (Sofia, Bulgaria), Institute for Physics of Condensed Matter (Braunschweig, Germany), and the Institute of Physics of Maria Curie-Sklodowska University (Lublin, Poland).

Lomonosov Moscow State University

Related Physics Articles:

Diamonds coupled using quantum physics
Researchers at TU Wien have succeeded in coupling the specific defects in two such diamonds with one another.
The physics of wealth inequality
A Duke engineering professor has proposed an explanation for why the income disparity in America between the rich and poor continues to grow.
Physics can predict wealth inequality
The 2016 election year highlighted the growing problem of wealth inequality and finding ways to help the people who are falling behind.
Physics: Toward a practical nuclear pendulum
Researchers from Ludwig-Maximilians-Universitaet (LMU) Munich have, for the first time, measured the lifetime of an excited state in the nucleus of an unstable element.
Flowers use physics to attract pollinators
A new review indicates that flowers may be able to manipulate the laws of physics, by playing with light, using mechanical tricks, and harnessing electrostatic forces to attract pollinators.
Physics, photosynthesis and solar cells
A University of California, Riverside assistant professor has combined photosynthesis and physics to make a key discovery that could help make solar cells more efficient.
2-D physics
Physicist Andrea Young receives a 2016 Packard Fellowship to pursue his studies of van der Waals heterostructures.
Cats seem to grasp the laws of physics
Cats understand the principle of cause and effect as well as some elements of physics.
Plasma physics' giant leap
For the first time, scientists are looking at real data -- not computer models, but direct observation -- about what is happening in the fascinating region where the Earth's magnetic field breaks and then joins with the interplanetary magnetic field.
Nuclear physics' interdisciplinary progress
The theoretical view of the structure of the atom nucleus is not carved in stone.

Related Physics Reading:

Basic Physics: A Self-Teaching Guide
by Karl F. Kuhn (Editor)

Seven Brief Lessons on Physics
by Carlo Rovelli (Author)

Fundamentals of Physics: Mechanics, Relativity, and Thermodynamics (The Open Yale Courses Series)
by R. Shankar (Author)

Physics Equations & Answers (Quick Study Academic)
by Mark Jackson (Author)

Physics: Principles with Applications (7th Edition) - Standalone book
by Douglas C. Giancoli (Author)

The Cartoon Guide to Physics (Cartoon Guide Series)
by Larry Gonick (Author)

No bullshit guide to math and physics
by Ivan Savov (Author)

Physics (5th Edition)
by James S. Walker (Author)

Physics
by David Young (Author), Shane Stadler (Author)

The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory
by Brian Greene (Author)

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

The Story Behind The Numbers
Is life today better than ever before? Does the data bear that out? This hour, TED speakers explore the stories we tell with numbers — and whether those stories portray the full picture. Guests include psychologist Steven Pinker, economists Tyler Cowen and Michael Green, journalist Hanna Rosin, and environmental activist Paul Gilding.
Now Playing: Science for the People

#487 Knitting in PEARL
This week we're discussing math and things made from yarn. We welcome mathematician Daina Taimina to the show to discuss her book "Crocheting Adventures with Hyperbolic Planes: Tactile Mathematics, Art and Craft for all to Explore", and how making geometric models that people can play with helps teach math. And we speak with research scientist Janelle Shane about her hobby of training neural networks to do things like name colours, come up with Halloween costume ideas, and generate knitting patterns: often with hilarious results. Related links: Crocheting the Hyperbolic Plane by Daina Taimina and David Henderson Daina's Hyperbolic Crochet blog...