This class is describes the anti-symmetric Dzyaloshinskii–Moriya interaction operator. More...

#include <SM_DMIOperator.h>

Inheritance diagram for SM_DMIOperator:

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Collaboration diagram for SM_DMIOperator:

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Public Member Functions
virtual CORE_UniquePointer< SM_SliceOperator >	NewInstance () const override
	create a New instance of this More...

virtual tMemSize	getMemorySize () const
	return the memory size of the class and the memory size of all its attributes/associations More...

virtual void	computeMagneticFieldSlice (const tIndex &timeIndex, const SM_Network &network, const SM_Material &material, const tIndex &startIndex, const tIndex &endIndex, const tReal S, const tBoolean &alpha, const tIndex &nH, tReal H) const
	compute the anisotropy magnetic field by virtual method More...

virtual tReal	computeSpinEnergy (const tIndex &i, const tIndex &timeIndex, const SM_Network &network, const SM_Material &material, const SM_RealField &S) const final
	compute the i-th spin heisenberg energy More...

virtual tReal	computeEnergySlice (const tIndex &timeIndex, const SM_Network &network, const SM_Material &material, const tIndex &startIndex, const tIndex &endIndex, const tReal *S) const
	compute the energy at time t by virtual method for all particles in [startIndex,endIndex[ More...

Public Member Functions inherited from SM_SliceOperator
virtual tMemSize	getContentsMemorySize () const
	return nthe memory size of the included associations More...

const tString &	getName () const
	return the operator name More...

virtual void	copy (const SM_SliceOperator &op)
	copy More...

virtual void	adimensionize (const tReal &cH)
	adimensionize operator with characteric field value in J More...

virtual void	discretize (const SM_Network &network, const SM_Material &material)
	discretize the operator on the network More...

virtual void	updateState (const tIndex &timeIndex, const SM_Network &network, const SM_Material &material, const SM_RealField &S)
	update the stae of the operator at time index More...

virtual tString	toString () const override
	return string representaton of the operator

Public Member Functions inherited from SM_Object
	SM_Object (void)
	create

virtual	~SM_Object (void)
	destroy

Public Member Functions inherited from CORE_Object
template<class T >
std::shared_ptr< T >	getSharedPointer ()
	return the shared pointer for this More...

template<class T >
std::shared_ptr< const T >	getConstSharedPointer () const
	return a const shared pointer for this More...

template<class T >
tBoolean	isInstanceOf () const
	test if the clas T is an instance of this class More...

tString	getClassName () const
	return the name of the class More...

tString	getPointerString () const
	retrun the pointer of the class as a string More...

tString	getIdentityString () const
	retrun the string identification of the class More...

Static Public Member Functions
static CORE_UniquePointer< SM_DMIOperator >	New ()
	build a new instance of the operator More...

static void	ComputeSpinEnergy (const tIndex &nNeighbors, const tIndex neighboringParticles, const tReal vD, const tBoolean &incD, const tReal S, const tReal Si, tReal &Ei)
	computes the exchange energy of a spin i and all its neighboring spins. More...

Static Public Member Functions inherited from CORE_Object
static tBoolean	EnableMemoryStack (const tBoolean &isMemoryChecked)
	enable the memory stack More...

static void	EnableMemoryStack ()
	enable the memory stack

static void	DisableMemoryStack ()
	disable the memory stack

static tBoolean	IsMemoryStackEnabled ()
	return trur if the memory stack is enabled

static tString	MemoryStackToString ()
	get the memory stack in string More...

static tIndex	GetRegisteredClassesNumber ()
	get the memory stack in string More...

Static Public Member Functions inherited from SM_LinearSliceOperator
static tReal	ComputeEnergy (const SM_Network &network, const SM_Material &material, const tIndex &startIndex, const tIndex &endIndex, const tReal S, const tInteger &nH, const tReal H)
	compute the energy by virtual method More...

Protected Member Functions
	SM_DMIOperator (void)
	create a network class

virtual	~SM_DMIOperator (void)
	destroy

Protected Member Functions inherited from SM_SliceOperator
	SM_SliceOperator (void)
	create a network class

virtual	~SM_SliceOperator (void)
	destroy

void	setName (const tString &name)
	set the name More...

Protected Member Functions inherited from CORE_Object
	CORE_Object ()
	build an instance of the object

virtual	~CORE_Object ()
	destroy the instance of object std

Protected Member Functions inherited from SM_LinearSliceOperator
	SM_LinearSliceOperator (void)
	create a network class

virtual	~SM_LinearSliceOperator (void)
	destroy

Detailed Description

This class is describes the anti-symmetric Dzyaloshinskii–Moriya interaction operator.

The DMI energy of a spin i is $ E_i= - \displaystyle \sum_{j \neq i} D_{ij} \cdot S_i \wegde S_j $

where $ D_{ij} $$ is expressed in Joules ( $J$).

In order to have $\displaystyle \forall i \in [0,P[, \forall k in [0,3[, H_k(P_i)=-\frac{1}{\mu_s} \frac{dE}{dS_i}(P_i).\delta_k$, where $ \delta k $ is the k-unit vector direction

the corresponding magnetic excitation field of the spin $ i$ is: $ H(P_i)=H^i=\frac{1}{\mu_s} \sum_{j \neq i} \S_j \wedge D_{ij} $.

The total DMI energy is the half of the sum of all spin energy in order not to take into accoung energy interaction between spin i and j twice and to verify the above relation which link the energy and the magnetic field:

$ E= - \frac{1}{2}. \displaystyle \sum_ i \sum_{j \neq i} D_{ij} S_i \wedge S_j $

The adimensionized formulation is :

$\tilde e=\mu_0.\mu_B^2. a^{-3}$
$\tilde h=\mu_0.\mu_B.a^{-3}$
$\tilde \mu_s=\frac{\mu_s}{\mu_B}$

where $a=10^{-10}m=1$ Angstrom, $\mu_B$ is the Bohr magneton $\mu_B=9.2740.10^{-24} J.T^{-1}$ and $\mu_0=4.\pi.10^{-7} T^2.J^{-1}.m^3 $ the vaccum permeability whe obtain: the general expression $ h=-\frac{1}{\tilde \mu_s} \frac{de}{dS_i}(P_i)$.

For the DMI operator it gives:

$ \tilde D_{ij}=\frac{D_{ij}.a^3}{\mu_B^2.\mu_0}$ and
$ e_i= - \displaystyle \sum_{j \neq i} \tilde D_{ij} <S_i, S_j> $ and
$<h_i(P_i),\delta_k>=\frac{1}{\tilde \mu_s} \sum_{j \neq i} \tilde D_{ij} \delta_k \wedge S_j $

The uml organization of the package is

Author: Stephane Despreaux

Version: 2.0

Member Function Documentation

◆ computeEnergySlice()

tReal SM_DMIOperator::computeEnergySlice	(	const tIndex &	timeIndex,
		const SM_Network &	network,
		const SM_Material &	material,
		const tIndex &	startIndex,
		const tIndex &	endIndex,
		const tReal *	S
	)		const

virtual

compute the energy at time t by virtual method for all particles in [startIndex,endIndex[

Parameters

[in]	timeIndex	: index of time
[in]	network	: network
[in]	material	: material of the network
[in]	startIndex	: start index of the particle to compute the energy
[in]	endIndex	: end index of the particle to compute the energy
[in]	S	unit direction of magnetic spin moment of size nParticles x dim

Returns: the energy of the operator It returns $ E=\frac{1/2} \sum_i E_i $

Implements SM_SliceOperator.

◆ computeMagneticFieldSlice()

void SM_DMIOperator::computeMagneticFieldSlice	(	const tIndex &	timeIndex,
		const SM_Network &	network,
		const SM_Material &	material,
		const tIndex &	startIndex,
		const tIndex &	endIndex,
		const tReal *	S,
		const tBoolean &	alpha,
		const tIndex &	nH,
		tReal *	H
	)		const

virtual

compute the anisotropy magnetic field by virtual method

Parameters

[in]	timeIndex	: time step index
[in]	network	: network
[in]	material	: material of the network
[in]	startIndex	: start index of the particle to compute the energy
[in]	endIndex	: end index of the particle to compute the energy
[in]	S	unit direction of magnetic spin moment of size nParticles x dim
[in]	alpha	sum operator 0 or 1
[in]	nH	number of elements of H
[in,out]	H	total magnetic field of size nH x dim

Computes $ H=alpha.H+H_{op} $

$ H_{op}= K. \nabla_{S_i} Phi(S_i,U) $

Implements SM_SliceOperator.

◆ computeSpinEnergy()

tReal SM_DMIOperator::computeSpinEnergy	(	const tIndex &	i,
		const tIndex &	timeIndex,
		const SM_Network &	network,
		const SM_Material &	material,
		const SM_RealField &	S
	)		const

finalvirtual

compute the i-th spin heisenberg energy

Parameters

[in]	i	: index of the spin
[in]	timeIndex	: time step index
[in]	network	: network
[in]	material	: material of the network
[in]	S	unit direction of magnetic spin moment of size nParticles x dim

Returns: the energy of the operator

Implements SM_SliceOperator.

◆ ComputeSpinEnergy()

static void SM_DMIOperator::ComputeSpinEnergy	(	const tIndex &	nNeighbors,
		const tIndex *	neighboringParticles,
		const tReal *	vD,
		const tBoolean &	incD,
		const tReal *	S,
		const tReal *	Si,
		tReal &	Ei
	)

inlinestatic

computes the exchange energy of a spin i and all its neighboring spins.

Parameters

[in]	nNeighbors	number of neighboring particles
[in]	neighboringParticles	indices of the neighboring particles of the particle i
[in]	vD	DMI energy factors per direction
[in]	incD	: increment on D values (0 for constant)
[in]	S	directions of the magnetic moment of all the spins
[in]	Si	begin iterator on direction of the spin i
[out]	Ei	energy of the spin $ E_i= - D_{ij}. \sum_{j=0}^{j=v-1} S_i \wedge S_j $

◆ getMemorySize()

virtual tMemSize SM_DMIOperator::getMemorySize ( ) const

inlinevirtual

return the memory size of the class and the memory size of all its attributes/associations

Returns

the memory size of the class and the memory size of its attributes/associations in bytes The mamory size is :

the added size of the base classes which contains:
- the primary attributes size depends on the order: (first delare the smallest attributes size
- all virtual functions costs <pointer-size> (4 32xor 8 64x) bytes by virtual function
- virtual inherihtance will increase of (4 or 8) bytes
we add the size of the contains values of the attributes : for example the size of a string is the length of the string 1 octet = 1 byte 1 Ko = 1024 bytes 1 Mo = 1024 Ko 1 Go = 1024 Mo

Reimplemented from SM_LinearSliceOperator.

◆ New()

static CORE_UniquePointer<SM_DMIOperator> SM_DMIOperator::New ( )

inlinestatic

build a new instance of the operator

Returns: an unique pointer of the operator

◆ NewInstance()

virtual CORE_UniquePointer<SM_SliceOperator> SM_DMIOperator::NewInstance ( ) const

inlineoverridevirtual

create a New instance of this

Returns: an unique pointer to the instance

Implements SM_SliceOperator.

The documentation for this class was generated from the following files:

/home/despreau/Developpement/CPP/devcpp20/include/stochmagnet/operators/dmi/SM_DMIOperator.h
/home/despreau/Developpement/CPP/devcpp20/src/stochmagnet/operators/dmi/SM_DMIOperator.cpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Member Function Documentation

◆ computeEnergySlice()

◆ computeMagneticFieldSlice()

◆ computeSpinEnergy()

◆ ComputeSpinEnergy()

◆ getMemorySize()

◆ New()

◆ NewInstance()