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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Novel disordering mechanism in ferromagnetic systems with competing interactions
Juan Carlos Andresen1, Creighton K Thomas, Helmut G Katzgraber
1Theoretische Physik, ETH Zurich, CH-8093 Zurich, Switzerland.
Physical Review Letters
|November 12, 2013
Summary
Ferromagnetic Ising systems are disordered by weak random fields due to a novel spin-glass mechanism. This finding challenges standard theories and explains experimental observations in magnetic materials.
Area of Science:
- Condensed matter physics
- Magnetism
- Disordered systems
Background:
- Ferromagnetic Ising systems with competing interactions are susceptible to disorder effects.
- The standard Imry-Ma argument predicts a higher critical random field for disordering.
Purpose of the Study:
- To investigate the effect of random fields on ferromagnetic Ising systems in three dimensions.
- To explain the experimental observations in LiHo(x)Y(1-x)F(4) regarding critical temperature and susceptibility broadening.
Main Methods:
- Theoretical analysis of ferromagnetic Ising systems with competing interactions and random fields.
- Consideration of an underlying spin-glass phase as a novel disordering mechanism.
- Application of the model to the specific case of LiHo(x)Y(1-x)F(4).
Main Results:
- A random field significantly smaller than the interaction strength can disorder the ferromagnetic phase in three dimensions.
- A novel disordering mechanism, triggered by an underlying spin-glass phase, is identified.
- The proposed mechanism explains the experimentally observed dependence of critical temperature and susceptibility broadening on random field strength.
Conclusions:
- The standard Imry-Ma argument is insufficient for general random-field systems.
- A new understanding of disordering in magnetic systems is provided, incorporating spin-glass effects.
- The findings offer a theoretical basis for recent experimental results in disordered magnetic materials.
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