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Updated: Jun 10, 2025

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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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Superconcentration for minimal surfaces in first passage percolation and disordered Ising ferromagnets
Barbara Dembin1, Christophe Garban2,3
1D-MATH, ETH Zürich, Rämistrasse 101, 8092 Zürich, Switzerland.
Summary
In first passage percolation, the maximal flow variance in a cylinder is superconcentrated. This finding also applies to the ground state energy of disordered Ising ferromagnets.
Area of Science:
- Probability Theory
- Statistical Mechanics
- Disordered Systems
Background:
- First passage percolation models are fundamental in understanding random processes on graphs.
- Superconcentration phenomena are crucial for analyzing the stability and behavior of complex systems.
- Disordered Ising ferromagnets exhibit complex magnetic properties influenced by random interactions.
Purpose of the Study:
- To investigate the maximal flow and minimal surfaces in a two-valued first passage percolation model on a cylinder.
- To prove the superconcentration of the maximal flow's variance.
- To establish an equivalent result for the ground state energy of a disordered Ising ferromagnet.
Main Methods:
- Adapting techniques inspired by Benjamini-Kalai-Schramm's proof for surface phenomena.
- Developing methods to control edge influences, overcoming limitations of previous averaging tricks.
- Analyzing minimal surfaces in a discrete setting, proving they cannot form long thin chimneys.
Main Results:
- Demonstrated superconcentration of the maximal flow variance in the cylinder for a specific parameter range.
- Showed that the ground state energy of a disordered Ising ferromagnet is superconcentrated under specific boundary conditions.
- Proved that discrete minimal surfaces cannot possess long thin chimneys, a result of independent interest.
Conclusions:
- The study establishes significant superconcentration results for maximal flow and ground state energy in a relevant percolation model.
- The findings have implications for understanding the behavior of disordered magnetic systems.
- The novel techniques developed offer new tools for analyzing related problems in probability and statistical physics.
Keywords:
Chaos and superconcentrationDisordered Ising ferromagnetsFirst passage percolationSurface fluctuationsMore Related Videos
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