FMR simulation in vampire

[AMRENDRA KUMAR]

Dear All,

I am trying to fmr simulation in vampire for NiFe. 
I have taken the all the parameters from the Richard Evans paper  given in Table 1.

Below is the snippet of codes I have used in my fmr simulation

The input file
--------------------------

sim:load-checkpoint=restart

create:crystal-structure = fcc

create:periodic-boundaries-x

create:periodic-boundaries-y

create:periodic-boundaries-z

dimensions:unit-cell-size = 3.48 !A

dimensions:system-size-x = 3 !nm

dimensions:system-size-y = 3 !nm

dimensions:system-size-z = 3 !nm

material:file = NiFe.mat

sim:temperature = 0

sim:time-steps-increment = 1000

sim:total-time-steps = 15000000

sim:time-step =1 !fs

sim:applied-field-unit-vector=1,0,0

sim:applied-field-strength= 0.30 !T

sim:fmr-field-strength = 0.001 !T

sim:fmr-field-frequency = 7.0

sim:fmr-field-unit-vector = 0,1,0

sim:program = fmr

sim:enable-fmr-field

sim:integrator = llg-midpoint

sim:save-checkpoint=end

output:real-time

output:applied-field-strength

output:material-magnetisation

The Material file> --------------------- #---------------------------------------------------
material:num-materials=2
#---------------------------------------------------
# Material 1 Ni (TM)
#---------------------------------------------------
material[1]:material-name=TM
material[1]:damping-constant=0.02
material[1]:exchange-matrix[1]=2.757e-21
material[1]:exchange-matrix[2]=2.8399e-21
material[1]:atomic-spin-moment=0.606 !muB
material[1]:uniaxial-anisotropy-constant=5.47e-26
material[1]:material-element=Ni
material[1]:minimum-height=0.0
material[1]:maximum-height=1.0
material[1]:host-alloy
material[1]:alloy-fraction[2]=0.20
material[1]:initial-spin-direction=random
material[1]:uniaxial-anisotropy-direction=1,0,0
#---------------------------------------------------
material[2]:material-name=FM
material[2]:damping-constant=0.02
material[2]:exchange-matrix[1]=2.8399e-21
material[2]:exchange-matrix[2]=6.25e-21
material[2]:atomic-spin-moment=2.22 !muB
material[2]:uniaxial-anisotropy-constant=5.65e-25
material[2]:material-element=Fe
material[2]:initial-spin-direction=random
material[2]:minimum-height=0.0
material[2]:maximum-height=0.0
material[2]:uniaxial-anisotropy-direction=1,0,0
But the resonance field is way higher than the reported value at 7 GHz which is around 600 Oe. But from my simulation I am getting around 1922 Oe. Can any one know the reason behind this ? Best Regards, Amrendra Kumar