PSCF v1.2
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This analyzer calculates the maximum amplitude of the second power of Fourier modes of exchange fields, referred to as the max order parameter. This analyzer is commonly used to identify order-disorder transition (ODT) in systems where the spontaneous phase transitions occur. In disordered phase, the max order parameter approaches to 0. In ordered phase, the max order parameter is a finite value.
\[ \Psi_{\text{max}} \equiv \max_{\bf G} \left[ W_{-}(\mathbf{G}) W_{-}(-\mathbf{G}) \right] \]
where \( \Psi_{\text{max}} \) denotes max order parameter, \( W_{-}(\bf G)\) denotes the Fourier components of the exchange field, and \(\bf G\) denotes the Fourier wavevector. Note, since \( W_{-} \) is real-valued function, \( W_{-}(\mathbf {G}) = W_{-}(-\mathbf{G}) \). The Fourier transformation is defined in Appendix: Periodic Functions and Fourier Series.
The full parameter file format, including all optional parameters, is shown below:
Meanings of the parameters are described briefly below:
Label | Description |
interval | number of steps between data samples |
outputFileName | name of output file |
hasAverage | whether the average and error analysis are needed? |
nSamplePerBlock | number of samples per block average |
During the simulation, \(\chi_b N \) and max order parameter are output to the file {outputFileName} every interval simulation steps.
At the end of the simulation, if hasAverage is true: