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Domain dynamics in Co/Pt/Co/Pt/Co/IrMn. M. Czapkiewicz. - PowerPoint PPT Presentation
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Domain dynamics in Co/Pt/Co/Pt/Co/IrMn
M. Czapkiewicz
New domain nucleation:N(t)=N0(1-exp(-Rt))
Fatuzzo: cylindric domains nucleation and growth B(t)=
exp(-2k2(1-(1 -(Rt+1/k) +0.5(Rt+1/k)2 –e-Rt(1-1/k) –0.5k2(1-Rt)))
where k=v/Rr,
v i R increase with z H, kconst R=R0exp[-(WN-2HMSVN)/kBT]
v=v0exp[-(WP-2HMSVP)/kBT]
k: real time
k: reduced time
0 5 10 15-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
- 20 mT- 19.0 mT- 18.7 mT- 18.2 mT- 18.1 mT- 17.5 mT- 17.1 mT- 16.2 mT- 15.6 mT- 15.2 mT- 14.2 mT- 13.3 mT
B [n
orm
aliz
ed
Time [sec]
-100% to -10.5%
0 1 2 3 4 50.0
0.2
0.4
0.6
0.8
1.0
-100% to -10.5%
- 20 mT- 19.0 mT- 18.7 mT- 18.2 mT- 18.1 mT- 17.5 mT- 17.1 mT- 16.2 mT- 15.6 mT- 15.2 mT- 14.2 mT- 13.3 mT
B(t
r)
t/t50
#26 backward
#26 forward
0 10 20 30 40 50 60 700.0
0.2
0.4
0.6
0.8
1.0
- 35.6 mT - 36.2 mT - 36.9 mT - 37.6 mT - 38.3 mT - 39.6 mT
B [N
orm
aliz
ed]
Time [sec]
+ 100% to -21%
0 2 40.0
0.2
0.4
0.6
0.8
1.0
+ 100% to -21%
- 35.6 mT - 36.2 mT - 36.9 mT - 37.6 mT - 38.3 mT - 39.6 mT
B(t
r)
t/t50
#26 backward
#26 forward
#26 real time
#31 forward – without dead time correction
0.0 0.2 0.4 0.6 0.8 1.0 1.2
0.0
0.2
0.4
0.6
0.8
1.0
47,07 mT 35,85 mT 33,92 mT 32,13 mT 30,35 mT 28,56 mT 26,6 mT 24,74 mT 22,89 mT 20,98 mT 18,97 mT 17,06 mT 15,2 mT 13,3 mT 11,4 mT 9,49 mT 7,70 mT 5,79 mT 3,85 mT
Ur [
No
rma
lize
d]
Time [s]
Sample # 31
0.00 0.25 0.50 0.75 1.00 1.25 1.50
0.0
0.2
0.4
0.6
0.8
1.0
47,07 mT 35,85 mT 33,92 mT 32,13 mT 30,35 mT 28,56 mT 26,6 mT 24,74 mT 22,89 mT 20,98 mT 18,97 mT 17,06 mT 15,2 mT 13,3 mT 11,4 mT 9,49 mT 7,70 mT 5,79 mT 3,85 mT
Ur
[No
rma
lize
d]
t/t50
Sample #31
#31 forward – dead time correction
#31 forward – fit after dead time correction
Kerr video: for H=21.1mT v=10m/s
#31 forward – before dead time correction – impossible to fit
#31 backward – fit after dead time correction
Kerr video: for H=7.8mT v=50m/s
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