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11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Local entropy and structure in a two-dimensional frustrated system.
Matthew D Robinson1, David P Feldman, Susan R McKay
1Red Shift Company LLC, 1017 E. South Boulder Road, Suite F, Louisville, Colorado 80027, USA. matthewd@mailaps.org
Chaos (Woodbury, N.Y.)
|October 7, 2011
Summary
Researchers probed order in a diluted Ising antiferromagnet using Shannon entropy. A phase transition was observed, revealing spin glass ordering and uneven entropy distribution across the lattice.
Area of Science:
- Condensed matter physics
- Statistical mechanics
- Information theory
Background:
- Quenched disorder introduces complexity in magnetic systems.
- Information theoretic measures can quantify order in complex systems.
- Diluted Ising antiferromagnets exhibit unique phase transitions.
Purpose of the Study:
- To investigate the role of quenched disorder in a diluted Ising antiferromagnet.
- To use Shannon and excess entropy as probes of order.
- To analyze the impact of sublattice dilution on magnetic ordering and entropy distribution.
Main Methods:
- Calculation of local contributions to Shannon entropy and excess entropy.
- Analysis of a diluted Ising antiferromagnet on a triangular lattice.
- Examination of temperature-driven phase transitions and sublattice magnetizations.
Main Results:
- A temperature-driven phase transition occurs in sufficiently diluted systems.
- The diluted sublattice exhibits spin glass ordering without net magnetization.
- Local entropy distributions broaden at low temperatures, indicating unequal entropy sharing.
- Local reentrance of entropy contributions observed in some regions.
- Average excess entropy peaks sharply at the critical temperature.
Conclusions:
- Shannon and excess entropy are effective quantitative probes of order from quenched disorder.
- Spin glass ordering significantly impacts entropy distribution and system dynamics.
- Excess entropy is sensitive to structural changes during phase transitions.
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