All Questions
Tagged with simulations ising-model
47
questions
2
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1
answer
72
views
What is this secondary transition in the simulation of the Ising model?
Here, the horizontal axis is the strength of the ambient magnetic field. The Hamiltonian I used is $$H = -h\sum_i \sigma_i - J\sum_{\langle i \, j \rangle}\sigma_i\sigma_j.$$ The horizontal axis is $h$...
- 487
2
votes
1
answer
920
views
Periodic autocorrelation function for Ising model?
I am trying to calculate the autocorrelation time for a 2-D Ising model Monte Carlo simulation. As the autocorrelation function, I am using $$\chi (t) = \frac{1}{t_{max}-t} \sum_{t' = 0}^{t_{max}-t-1} ...
- 65
0
votes
1
answer
240
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Weird results of Monte Carlo simulation
I'm simulating the 3D Ising Model using the Wolff update algorithm.
I am using the Mersenne Twister RNG.
When the lattice size is $L = 50$, the specific heat curve looks very weird!!
I want to ...
- 55
1
vote
1
answer
120
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Why are simulations like Monte Carlo or Metropolis studied for Ising Models when 1d and 2d case have analytical solutions?
I know that absolute analytical solutions exist for the 1d and 2d case but need some intuition as to why these simulation algorithms are used and how do we benefit from them ?
- 21
1
vote
1
answer
652
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Flipping more than one spin in Metropolis Monte Carlo algorithms
In lattice systems such as Ising model or spin glasses, the standard Monte Carlo simulation with Metropolis algorithm works by proposig a single spin flip and then accepting or rejecting the proposal ...
- 386
2
votes
1
answer
2k
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Monte Carlo steps in Ising model Metropolis algorithm
In K.Binder's book Monte Carlo Simmulation in Statistical Physics 4th ed., one Monte Carlo step is defined as "one sweep through the lattice". However, in many other books and papers, the Monte Carlo ...
- 369
0
votes
0
answers
127
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What is order of the Wolff Cluster algorithm?
What is the order of the Wolff Cluster update algorithm for Ising Model 2D and 3D?
- 55
0
votes
1
answer
140
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New to ising model, can't find answer to simple energy calculation
I'm trying to see why we get this energy config here
As far as I understood, up/down or down/up contributes +, and same direction, ie up up or down down negative. So it should be all negative on the ...
0
votes
0
answers
708
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Critical slowing down in Monte-Carlo algorithm for classical 2D Ising Model
Why do local updates (i.e. local spin flips) near the phase transition in MC algorithm for classical 2D Ising model are said to be not "effective" and lead to incorrect critical indices? I understand ...
- 163
1
vote
1
answer
236
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$\Delta E=0$ in $2$D Ising model - accept or not?
2D Ising model simulation using the Metropolis algorithm.
There is one thing which I don't understand.
The difference in energy $\Delta E$ between the initial state and the new state is:
$\Delta E = ...
- 165
1
vote
1
answer
276
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Ising simulation-dimensionless
My question is about dimensions in Ising model.When we want to simulate Ising we use dimensionless parameter as you know.We choose J to be 1 and also K equal 1 and when temperature is 2.26 then it's ...
- 325
7
votes
1
answer
2k
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Critical temperature and lattice size with the Wolff algorithm for 2d Ising model
When I run my implementation of the Wolff algorithm on the square Ising model at the theoretical critical temperature I get subcritical behaviour. The lattice primarily just oscillates between mostly ...
- 3,500
2
votes
1
answer
2k
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I'm getting weird autocorrelations when simulating an Ising model below the critical temperature
So I'm simulating an Ising model using Monte Carlo and the Metropolis algorithm. After letting it reach equilibrium, I try to calculate the autocorrelation of the magnetization. As long as the system ...
- 163
9
votes
2
answers
5k
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Numerical Ising Model - Wolff algorithm and correlations
I'm doing some numerical Monte Carlo analysis on the 2 dimensional Ising model at the critical point. I was using the Metropolis 'single flip' evolution at first with success, though it suffers from ...
1
vote
0
answers
2k
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2D Ising model simulations: Wolff algorithm acceptance probability with an external magnetic field
I have implemented the Wolff algorithm to simulate a 2D ferromagnet. It works by building a cluster of like spins and flipping them all at once to move quickly through phase space. In the case of no ...
- 439