Related Experiment Video
Updated: Mar 12, 2026
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
8.7K
Field-Tuned Order by Disorder in Frustrated Ising Magnets with Antiferromagnetic Interactions.
P C Guruciaga1, M Tarzia2, M V Ferreyra3
1Instituto de Investigaciones Físicas de Mar del Plata (IFIMAR), UNMdP-CONICET, 7600 Mar del Plata, Argentina.
Physical Review Letters
|October 30, 2016
Summary
We show how thermal fluctuations select magnetic order in frustrated Ising pyrochlores. This order-by-disorder transition, observed in specific materials, can be detected via finite-size effects.
Area of Science:
- Condensed Matter Physics
- Magnetism
- Thermodynamics
Background:
- Ising pyrochlores exhibit complex magnetic behavior due to geometric frustration.
- Applied magnetic fields can frustrate antiferromagnetic order, leading to exotic phases.
- Order-by-disorder phenomena involve thermal fluctuations selecting a specific ground state.
Purpose of the Study:
- To demonstrate and characterize the thermal order-by-disorder transition in Ising pyrochlores.
- To quantitatively link thermal excitations to the selection of symmetry-broken states.
- To explore experimental detection methods for this transition.
Main Methods:
- Mean-field cluster variational method
- Low-temperature expansion
- Monte Carlo simulations
- Direct evaluation of the density of states
Main Results:
- Demonstrated the appearance of thermal order by disorder in Ising pyrochlores under magnetic fields.
- Quantitatively showed how thermal excitations select a symmetry-broken state.
- Identified anomalous finite-size effects relevant for experimental detection.
Conclusions:
- Thermal fluctuations play a crucial role in selecting magnetic order in frustrated systems.
- The findings are relevant for both 2D and 3D magnetic materials.
- Experimental detection in materials like Nd2Hf2O7 and Nd2Zr2O7 is proposed.
Related Concept Videos
01:31Ferromagnetism
3.4K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
3.4K
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
1.7K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.7K
01:23Atomic Nuclei: Nuclear Relaxation Processes
1.3K
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
1.3K
01:27Magnetic Fields
7.7K
A moving charge or a current creates a magnetic field in the surrounding space, in addition to its electric field. The magnetic field exerts a force on any other moving charge or current that is present in the field. Like an electric field, the magnetic field is also a vector field. At any position, the direction of the magnetic field is defined as the direction in which the north pole of a compass needle points.
A magnetic field is defined by the force that a charged particle experiences...
A magnetic field is defined by the force that a charged particle experiences...
7.7K
02:42Valence Bond Theory
11.5K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
11.5K
02:58Crystal Field Theory - Octahedral Complexes
31.5K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
31.5K