Nematic order in a simple-cubic lattice-spin model with full-ranged dipolar interactions
Hassan Chamati1, Silvano Romano2
1Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussée, 1784 Sofia, Bulgaria.
Physical Review. E
|June 15, 2016
Summary
This study compares two lattice models with dipolarlike interactions. Both models exhibit order by disorder, but differ in ground-state energy and critical exponents, aligning with theoretical predictions.
Area of Science:
- Statistical Mechanics
- Condensed Matter Physics
- Lattice Models
Background:
- Previous work analyzed a truncated nearest-neighbor interaction model.
- This study examines the full-ranged interaction counterpart for comparison.
Purpose of the Study:
- Investigate the critical behavior of the full-ranged dipolar lattice model.
- Compare its properties with the truncated model.
- Analyze the role of thermal fluctuations in ordering.
Main Methods:
- Mathematical proof of ordering transition.
- Analysis of ground-state configurations.
- Comparison of critical exponent estimates.
Main Results:
- Both models show degenerate ground states with orientational order.
- Nematic order emerges at low temperatures via order by disorder.
- Quantitative differences in ground-state energy and critical exponents were observed.
Conclusions:
- The full-ranged model's critical behavior is consistent with theoretical and experimental findings.
- The order by disorder mechanism is robust across both models.
- Quantitative discrepancies highlight nuances in interaction range effects.
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