Precession

class micromagneticmodel.Precession(**kwargs)

Precession dynamics term.

\[\frac{\text{d}\mathbf{m}}{\text{d}t} = -\frac{\gamma_{0}}{1 + \alpha^{2}} \mathbf{m} \times \mathbf{H}_\text{eff}\]

Parameters:

gamma0 (numbers.Real, dict, discretisedfield.Field) – If a single unsigned value numbers.Real is passed, a spatially constant parameter is defined. For a spatially varying parameter, either a dictionary, e.g. gamma={'region1': 1e5, 'region2': 5e5} (if the parameter is defined “per region”) or discretisedfield.Field is passed.

Examples

1. Defining the precession dynamics term using scalar.

>>> import micromagneticmodel as mm
...
>>> precession = mm.Precession(gamma0=mm.consts.gamma0)

2. Defining the precession dynamics term using dictionary.

>>> precession = mm.Precession(gamma0={'region1': 1e5, 'region2': 2e6})

3. Defining the precession dynamics term using discretisedfield.Field.

>>> import discretisedfield as df
...
>>> region = df.Region(p1=(0, 0, 0), p2=(5e-9, 5e-9, 5e-9))
>>> mesh = df.Mesh(region=region, n=(5, 5, 5))
>>> gamma0 = df.Field(mesh, nvdim=1, value=5e5)
>>> precession = mm.Precession(gamma0=gamma0)

4. An attempt to define the precession dynamics term using a wrong value.

>>> precession = mm.Precession(gamma0=-5)  # negative value
Traceback (most recent call last):
...
ValueError: ...

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Methods

__add__	Binary + operator.
__dir__	Default dir() implementation.
__eq__	Relational operator ==.
__iter__	Iterator.
__repr__	Representation string.
dmdt

Properties

gamma0	Descriptor allowing setting attributes with a value described as descriptor or a dictionary.
name	Name.

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