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[ Identification | Description | Input parameters | Links ]
The SpinWave_BCO Component
A sample for FM and AFM magnon scattering from a oI lattice based on cross section expressions from Marshall and Lovesey ch.9.
Identification
- Site:
- Author: Silas Schack (algorithm based on "Phonon_simple" by Kim Lefmann)
- Origin: NBI
- Date: 13.06.25
Description
Single-cylinder shape. Absorption included. No multiple scattering. No incoherent scattering emitted. No attenuation from coherent scattering. No Bragg scattering. Bravais lattice only. (i.e. just one spin per sublattice unit cell) Algorithm: 0. Always perform the scattering if possible (otherwise ABSORB) 1. Choose direction within a focusing solid angle 2. Choose mode seperated by applied B-field 3. Calculate the zeros of (E_i-E_f-hbar omega(kappa)) as a function of k_f 4. Choose one value of k_f (always at least one is possible!) 5. Perform the correct weight transformation
Input parameters
Parameters in boldface are required; the others are optional.| Name | Unit | Description | Default | |
| radius | m | Outer radius of sample in (x,z) plane | ||
| yheight | m | Height of sample in y direction | ||
| sigma_abs | barns | Absorption cross section at 2200 m/s per atom | 1 | |
| sigma_inc | barns | Incoherent scattering cross section per atom | 0 | |
| a1 | AA | Lattice constants of orthorhombic body centred lattice | ||
| a2 | AA | Lattice constants of orthorhombic body centred lattice | ||
| a3 | AA | Lattice constants of orthorhombic body centred lattice | ||
| j | meV | Coupling constant to body centered spins | ||
| ja | meV | Coupling constant to nearest neighbours along a | ||
| jb | meV | Coupling constant to nearest neighbours along b | ||
| jc | meV | Coupling constant to nearest neighbours along c | ||
| j_110 | meV | Coupling constant to nearest neighbours +x+y | 0 | |
| j_110_prime | meV | Coupling constant to nearest neighbours +x-y | 0 | |
| S | 1 | Spin of magnetic ions | ||
| D | meV | Uniaxial anisotropy; easy axis is c-axis. Non-positive value assumed | ||
| B | T | Field strength of external magnetic field applied along z-axis | ||
| FM | 1 | Tag for ferromagnetic system if FM==1 | 0 | |
| Fq | 1 | Magnetic form factor | 1 | |
| mode_input | 1 | Index of mode(s) to simulate | 2 | |
| DW | 1 | Debye-Waller factor | 1 | |
| T | K | Temperature | ||
| e_steps_low | 1 | Number of low-energy steps in zrid | ||
| e_steps_high | 1 | Number of high-energy steps in zrid | ||
| target_x | m | Position of target to focus at. Transverse coordinate | 0 | |
| target_y | m | Position of target to focus at. Vertical coordinate | 0 | |
| target_z | m | Position of target to focus at. Straight ahead. | 0 | |
| target_index | 1 | Relative index of component to focus at, e.g. next is +1 | 0 | |
| focus_r | m | Radius of sphere containing target. | 0 | |
| focus_xw | m | Horiz. dimension of a rectangular area | 0 | |
| focus_yh | m | Vert. dimension of a rectangular area | 0 | |
| focus_aw | deg | Horiz. angular dimension of a rectangular area | 0 | |
| focus_ah | deg | Vert. angular dimension of a rectangular area | 0 | |
| verbose | 1 | Verbosity level | 0 |
| AT ( | , | , | ) RELATIVE | |||
|---|---|---|---|---|---|---|
| ROTATED ( | , | , | ) RELATIVE |
Links
- Source code for
SpinWave_BCO.comp.
[ Identification | Description | Input parameters | Links ]
Generated on mcstas 3.7.1
