Dipolar Ising model: Phases, growth laws, and universality
Shikha Kumari1, Sanjay Puri1, Varsha Banerjee2
1School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
Physical Review. E
|September 16, 2021
Summary
Dipolar interactions in magnetic solids and superlattices are complex. Our study reveals universal domain growth dynamics across all phases of the dipolar Ising model, despite interaction anisotropy.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
- Materials Science
Background:
- Dipolar interactions govern the behavior of magnetic and dielectric solids, and magnetic superlattices.
- These interactions are anisotropic and long-ranged, leading to complex magnetic order and glassy dynamics.
- The dipolar Ising model (DIM) with exchange (J) and dipolar (D) interactions captures these systems, exhibiting four distinct phases based on interaction strength (Γ=J/D).
Purpose of the Study:
- To investigate domain growth or coarsening dynamics in the three-dimensional dipolar Ising model (d=3 DIM) under deep quenches.
- To address the challenge of theoretically handling anisotropic and long-range dipolar interactions in nonequilibrium phenomena.
- To explore the universality of ordering dynamics across different magnetic phases within the DIM.
Main Methods:
- Utilizing Monte Carlo simulations to model the d=3 dipolar Ising model.
- Implementing deep quench protocols to initiate and observe domain growth.
- Analyzing the dynamics of domain coarsening in various magnetic phases.
Main Results:
- Observed universal behavior in the ordering dynamics across all four distinct magnetic phases of the DIM.
- Demonstrated that domain growth dynamics are consistent despite the anisotropy of interactions and diverse ground state configurations.
- Provided insights into a challenging nonequilibrium phenomenon previously difficult to address theoretically.
Conclusions:
- The ordering dynamics in the dipolar Ising model exhibit a universal character, irrespective of the specific magnetic phase or ground state configuration.
- This universality simplifies the understanding of complex magnetic systems governed by dipolar interactions.
- The study highlights the effectiveness of Monte Carlo simulations for investigating nonequilibrium phenomena in condensed matter systems.
More Related Videos
Related Concept Videos
01:30Current Growth And Decay In RL Circuits
4.1K
The current growth and decay in RL circuits can be understood by considering a series RL circuit consisting of a resistor, an inductor, a constant source of emf, and two switches. When the first switch is closed, the circuit is equivalent to a single-loop circuit consisting of a resistor and an inductor connected to a source of emf. In this case, the source of emf produces a current in the circuit. If there were no self-inductance in the circuit, the current would rise immediately to a steady...
4.1K
01:28Bacterial Growth Curve
1.1K
The bacterial growth curve is a fundamental concept in microbiology that describes the dynamics of bacterial population growth in a closed system with controlled environmental conditions, such as temperature and nutrient availability. This curve is divided into four distinct phases: lag, log (exponential), stationary, and death phases, each reflecting a unique stage of bacterial adaptation and growth. During the lag phase, bacteria acclimate to their surroundings by synthesizing essential...
1.1K
02:36Cells Coordinate Growth and Proliferation
4.7K
Cell size is a significant factor impacting cellular design, function, and fitness. There exists some internal coordination by which cells double their masses before division, thus, achieving homeostasis. Coordination between cell growth and proliferation depends on the checkpoints in between cell cycle phases. Loss of coordination or failure in the checkpoint mechanism can drive the cell to uncontrolled growth and loss of cellular function. Like dividing cells that coordinate cellular growth,...
4.7K
01:19Cyclic Processes And Isolated Systems
3.0K
A thermodynamic system with zero heat exchange and work is an isolated system. For these systems, the internal energy remains constant.
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each...
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each...
3.0K
02:31Phase Transitions
20.9K
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to...
20.9K
01:28Induced Electric Dipoles
4.5K
A permanent electric dipole orients itself along an external electric field. This rotation can be quantified by defining the potential energy because the external torque does work in rotating it. Then, the potential energy is minimum at the parallel configuration and maximum at the antiparallel configuration. While the former is a stable equilibrium, the latter is an unstable equilibrium.
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
4.5K